Your email address will not be published. This means the engine is producing less power and, therefore, less vacuum. However, don't disengage your ears. I run a Q/F 650 mechanical and my set screws are about 3/4 out. 20 degrees at idle? Most engines will run 17-21 In/Hg while idling at normal operating temperature.
I need an opinion from all you pros out there! Do Not Sell My Personal Information -, By logging into your account, you agree to our. A vacuum gauge is irreplaceable when tuning a carburetor. I no longer run it on the MSD dizzy and can't say I miss in terms of drivability or MPG.
Engine RPM bouncing around with vacuum ranging between 10 and 20 are symptoms of weak valve guides. resivor can. Notify me of follow-up comments by email. Bouncing could be indicative of another problem. Keep in mind, this reading is ideal for stock-cammedengines running at sea level. Next, go for a test drive. What could it be. Contact Us - If that is where you get your highest vac number than it is the best mixture for your engine. EZ EFI 2.0. I hate to ponder pulling our fresh install to change out the Sofa hit it on the head. The needle on my vac gauge moves about an inch or two until you are accelerating then it is smooth, on decal and light acceleration I see about 12". Do you have a way to tune the fuel table?
Come join the discussion about performance, racing, conversions, modifications, troubleshooting and drivetrain. About Us - out if kilter. Slightly lower could idle a little better. In 2012, he helped establish OnAllCylinders, where he enjoys covering all facets of hot rodding and racing. Mother thumper cam For comparison, 496 stroker w 230/236 duration at .050, .541 lift hydraulic roller, at 14 initial and 900 rpm, 12 inHg. Learn how your comment data is processed. At a faster idle speed the vacuum will increase. a SBC, but only if all the parts were perfectly matched. It is a Howard's 250021-11 cam that says Ford FE on the card profile.
[] the engine passes the leakdown test, start looking for vacuum leaks. Then I learned how to adjust that on my Mallory dist. Once you find it, that can be used to figure out the proper power valve. http://www.onallcylinders.com/2015/0gine-problems/ [], Excellent information, more complete that what came with my vacuum gage. Releasing the accelerator quickly after a few seconds should cause vacuum to quickly bounce back up to above normal (usually around 25 in/Hg) then quickly return to normal (17-21 /Hg) as engine RPM slowly returns to idle. Well, I have been fiddling with the truck today, and I can't coax a reading of more than 16/17 out of it at idle in park (750 rpm). To get started youll need to hook your vacuum gauge to an intake manifold vacuum source. If you are running a PCV, eliminate it. Very interesting,happy to know Im not running to lean,tried using the vac. The following errors occurred with your submission. An extremely low reading could also indicate an air leak at the intake manifold or throttle body. Holley 750DP I havnt drove the pick up yet, waiting for the registration to come through.
next step. Very informative. Good luck! How about that bitchin' Howard's Cam sticker? A vacuum leak will suck the carb cleaner into the engine and cause the RPM to fluctuate rapidly. Finally after hours of trial & error it started with the carb unplugged Your correct,with 224 deg dur @.05 in 350 cubes you should not have 21" idle vaccum . never started. My machine shop guy really likes Howard's Cams, and that is what he wanted to put in. He has also partnered with mainstream and trade publications on a wide range of editorial projects. The Fora platform includes forum software by XenForo, VerticalScope Inc., 111 Peter Street, Suite 600, Toronto, Ontario, M5V 2H1, Canada. and a vacumn gauge next to my tachometer. It barely It may not display this or other websites correctly. was 3-7 inches. Put these three pieces of information together and youll know if youre looking at an easy fix or a complete engine rebuild. Turn very slowly and stop turning as soon as vacuum stop climbing or drops, then repeat the process on the other side if required. The aluminum Trick Flow 2.02 heads needed work and a couple springs that were weak.
God bless you, Sir. Terms of Service - Needle fluctuating under accelaration i notice is one of the diagnosis, what if on idle and revved a few times, that normal? Cookie Policy - The most I've seen in a big solid cam is 17". with NO vacumn hooked to carb and the carb port was plugged. March 19, 2019 Opening the idle screws more does not effect vacuum or quality but AF goes richer at 12:1. When I was a kid, my father and BJ taught me how to adjust a new or rebuilt carburetor by watching and listening to the engine. I said that I did a compression test and that all is at the right. Its high idleling and it has a code p0300 which is random misfire where should i start. A stock cam has will probably give higher readings. Once on the throttle 11 to 12 A/F, I am generally too rich.
I always read about how a big cam will give you lower vacuum numbers at idle. How much vacuum are you guys seeing at idle? I just lowered the idle as far down as I could get it without stalling. A good source for many is the vacuum line going to the transmission. Higher elevations may cause slightly lower readings. If the needle drops quickly and returns to a normal reading, a burnt or sticky valve is indicated. Need other technical information or engine specific advice? I like to push the hose on my vacuum gauge through the firewall/bulkhead (using an existing penetration) and connect it to a direct vacuum source like the manifold (more on this later) so I can watch my vacuum gauge as Im test driving the vehicle. The engine seems really cold blooded, and takes its sweet time to warm up. Has mild rv cam. Repeat on the other side if required. Kim. VP 5.7GSI wont start - good fuel pressure, good ecm, wiring - Page 53, Vac Visual: Quick Guide to Vacuum Gauge Readings - OnAllCylinders, Vac Visual: Quick Guide to Vacuum Gauge Readings | MEP Precision Racing, Can Low Compression Cause a Lean Engine Condition Like This? Should be able to get down to 750 with a cam like that (stock was 650). Do Not Sell My Personal Information -, By logging into your account, you agree to our. It was set to deliver 10* advance at part throttle above 8" of vacuum.
Next I would have never recommend such a large cam for street use not worth the hassel, I have a 292 cam and that has to be the dummiest thing one can do to a street engine. " It could be a vacuum leak or fuel drip, but check your valve lash. I have the solid roller version of the XE274 cam (236 @ .050) and am getting a solid 14" of vacuum at a 750 RPM idle. FFR 5353K, 408W, TKO 500, 2015 IRS w/ 315 gear, Breeze QA1 DA coilovers front and rear, APE hardtop, Forte front swaybar. It takes a 10 minutes to get the vacuum up to at least 15. Check the simple (inexpensive) things first like your pcv and breather to ensure they're not pulling oil before you suspect a port leak in the lifter valley. Not a good cam to start with, especially with only 9-1 compression. As stated, a stock engine should pull 17-21 In/Hg of vacuum at idle. Hello,
I have a vacuum gauge and A/F meter in my dash so I see these readings all the time. A full-blooded Native American Indian, hed often climb up after me into an engine bay (he was only five feet tall) to do stuff and explain what he was doing and why he was doing it. hallo mijn vacuum meter meet een snelle trilling boven de 20 inch Is this normal for a cam with an intake duration of 230 degrees and a lift of .48 inches? and vacuum circuit, HELP! The cool thing about using a vacuum gauge to diagnose engine problems is that different engine problems show themselves by vacuum readings in different ranges. Common causes of steady low reading are blowby due to worn piston rings or possibly late ignition or valve timing. You likely have a restriction somewhere within your exhaust system or a damage exhaust component. Make sure any ports or fittings that are supposed to be plugged are plugged properly. 17" isn't too bad, but there are some things to check. Years ago, my fathers main mechanic at the Chevron station, Billy Jeff BJ gave me a vacuum gauge as a birthday present. lift .673/.648, @.020 286/286, @.050 250/254 lobe at 107 centerline at 105. It is definitely not a stock cam. Using Engine Vacuum to Diagnose Performance Issues, 15-18 /Hg and holding steady the timing is retarded too much; advance, holding steady at 10-15 /Hg indicates valve mechanical timing issues, the, very low but steady readings of 5-10 In/Hg are indicative of a leaking. What can this be? Carb Size Street Car - Advantage of QF 780 cfm over 735 cfm? Needle steady and increases at acceleration. I agree to receive emails from the site. A couple of years later I realized that I got 20 deg of advance at full vacuum. To confirm, youll need to perform a compression test. 340 degrees advertised. Come join the discussion about performance, production numbers, VIN decoders, modifications, troubleshooting, power adders, DIY tutorials, and more! Privacy Policy. As I did some serious homework Terms of Service - Gremlins in the Thermoquad ? Comp Cams Mother thumper cam for something that WORKS.. With that much duration and low vacuum, it is just a massive vacuum leak. Start the engine and listen for leaks in several locations around the engine bay. Solid roller lunati 51019 with a 1.7 shaft mount rocker setup, put cam at about 256/264 @.050, .650" lift. I have a rapid fuctuattion between 14 and 15. I haven't checked it so i dont know what its at. "What vacuum reading is okay with a lumpy cam? document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Alcohol Injected All Alum 632 cid Race Engine, BLOCKS-BLOCKS-BLOCKS in Stock Ready to Ship, Everything You Need to START a Chevy Performance Connect & Cruise System (LS and LT Engines), What To Look For When Your Hot Rod or Restoration Doesnt Start, An LS3 Swapped 1992 Buick Roadmaster Estate Wagon Project: Part Five. If you notice the needle slowly fluctuating between four or five inches, chances are you have an ignition-related issue. Begin your engine check-up by making a thorough preliminary inspection. The swing on the gauge is usually anywhere from 10 to 22 inches of mercury, depending on the speed of the engine. JavaScript is disabled. Please tell me if thats the proper This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register. Yours may be missing or old. The following errors occurred with your submission, 1967 - 1972 F-100 & Larger F-Series Trucks, Lightning, Harley-Davidson F-150, Roush F-150 & Saleen F-150, Conventional (Bumper Pull) Towing; Travel Trailers & Pop-ups, Toy Hauler Towing; Fifth Wheel & Bumper Pull, Flatbed, Car, Boat, Utility, Horse & Misc.
For good power brakes you will need at least 14 to 16 of vacuum. I would say that you are not too lean.
Increasing the idle speed to 1000 gives another 1" and decreasing it to 800 drops another 1". What cam are you running? Thanks Tedster! Trick Flow 2.02 Heads For every 1,000 feet above sea level, you can expect the reading to be about one inch lower. Edelbrock Air Gap manifold Very interesting to a Chevrolet fanatic that probably could assemble Steve,you are correct the idle vac will come down some when he reduces the idle speed but a 650 rpm idle is for auto trans in gear/not when in paryk where ot would idle higher & many manual trans setups idle in the 750-800+ rpm range. Post it here! I tried connecting to manifold once and it was terrible. A little low on the scale but good..(a steady reading). I have about 13 deg vacuum at idle, and always seem to be 13.5 to 14 A/F. I know on my setup if it is too fat at idle and i lean it out, the map sensor will start showing more engine vacuum where the engine actually wants to idle with less fuel. No matter where you get your vacuum source, make sure its not ported. You should never scrimp on your vacuum gauge. Come join the discussion about restorations, builds, performance, modifications, classifieds, troubleshooting, maintenance, and more! Low quality gauges can leak internally and give unreliable readings. Its so valuable, in fact, that OnAllCylinders contributor Lori Sams put together thisvisual cheat sheet to help youunderstand common gauge readings. For example, if youre seeing vacuums readings at idle of: Fluctuations in vacuum with the engine idling at operating temperature are indicative of either an engine misfire or a problem with a valve. Carb tuning is part art and part science. We discuss MK4, GTM, 818, Type 65 coupe, roadsters, and more! Adjust the rockers, My dodge charger has a higher than normal reading on the vacuum gauge its obove 25. The engine seems really cold blooded, and takes its sweet time to warm up.
That is going in the rear window tomorrow! When diagnosing engine performance problems using vacuum, you must use a direct source of vacuum, such as the vacuum tap on most intake manifolds. He's done pretty much everything in the automotive aftermarket from gas station island attendant, parts counter, mechanic, and new and used sales. idles at 950-1050 rpm. You are using an out of date browser. The ballast wire drops the voltage down, but the reason for that is to reduce the current that flows through the primary ignition circuit. Idle is 9" vacuum at 1100rpm. Solved. But, I also wonder if a larger cam is also playing a role in the lower vacuum readings. Archive - You ought to be pig rich in gear at idle and Everytime you mildly take off. Terms of Service - Don't see another board for your problem? hello, sorry for my writing I am French, I have a pontiac firebird 2.8l manual transmission of 1988 and on my vacuum gauge I read 16 hg with the occasion very slight increase to 16.5 hg and after having all check all the ignition it turns out that all works well and with the good advance besides if I try to advance the ignition i have a misfire can someone have an idea? Since its hopefully a fine instrument, treat it properly.
Steady vacuum is good.
Mike Aguilar I put it on the dash above the speedo so I can see the fluctuations as Im driving and link them to the driving conditions under which they occurred. advance,didnt work for me,lots, Found my problem,long story short,took a long drive That mix.
I need an opinion from all you pros out there! Do Not Sell My Personal Information -, By logging into your account, you agree to our. A vacuum gauge is irreplaceable when tuning a carburetor. I no longer run it on the MSD dizzy and can't say I miss in terms of drivability or MPG.
Engine RPM bouncing around with vacuum ranging between 10 and 20 are symptoms of weak valve guides. resivor can. Notify me of follow-up comments by email. Bouncing could be indicative of another problem. Keep in mind, this reading is ideal for stock-cammedengines running at sea level. Next, go for a test drive. What could it be. Contact Us - If that is where you get your highest vac number than it is the best mixture for your engine. EZ EFI 2.0. I hate to ponder pulling our fresh install to change out the Sofa hit it on the head. The needle on my vac gauge moves about an inch or two until you are accelerating then it is smooth, on decal and light acceleration I see about 12". Do you have a way to tune the fuel table?
Come join the discussion about performance, racing, conversions, modifications, troubleshooting and drivetrain. About Us - out if kilter. Slightly lower could idle a little better. In 2012, he helped establish OnAllCylinders, where he enjoys covering all facets of hot rodding and racing. Mother thumper cam For comparison, 496 stroker w 230/236 duration at .050, .541 lift hydraulic roller, at 14 initial and 900 rpm, 12 inHg. Learn how your comment data is processed. At a faster idle speed the vacuum will increase. a SBC, but only if all the parts were perfectly matched. It is a Howard's 250021-11 cam that says Ford FE on the card profile.
[] the engine passes the leakdown test, start looking for vacuum leaks. Then I learned how to adjust that on my Mallory dist. Once you find it, that can be used to figure out the proper power valve. http://www.onallcylinders.com/2015/0gine-problems/ [], Excellent information, more complete that what came with my vacuum gage. Releasing the accelerator quickly after a few seconds should cause vacuum to quickly bounce back up to above normal (usually around 25 in/Hg) then quickly return to normal (17-21 /Hg) as engine RPM slowly returns to idle. Well, I have been fiddling with the truck today, and I can't coax a reading of more than 16/17 out of it at idle in park (750 rpm). To get started youll need to hook your vacuum gauge to an intake manifold vacuum source. If you are running a PCV, eliminate it. Very interesting,happy to know Im not running to lean,tried using the vac. The following errors occurred with your submission. An extremely low reading could also indicate an air leak at the intake manifold or throttle body. Holley 750DP I havnt drove the pick up yet, waiting for the registration to come through.
next step. Very informative. Good luck! How about that bitchin' Howard's Cam sticker? A vacuum leak will suck the carb cleaner into the engine and cause the RPM to fluctuate rapidly. Finally after hours of trial & error it started with the carb unplugged Your correct,with 224 deg dur @.05 in 350 cubes you should not have 21" idle vaccum . never started. My machine shop guy really likes Howard's Cams, and that is what he wanted to put in. He has also partnered with mainstream and trade publications on a wide range of editorial projects. The Fora platform includes forum software by XenForo, VerticalScope Inc., 111 Peter Street, Suite 600, Toronto, Ontario, M5V 2H1, Canada. and a vacumn gauge next to my tachometer. It barely It may not display this or other websites correctly. was 3-7 inches. Put these three pieces of information together and youll know if youre looking at an easy fix or a complete engine rebuild. Turn very slowly and stop turning as soon as vacuum stop climbing or drops, then repeat the process on the other side if required. The aluminum Trick Flow 2.02 heads needed work and a couple springs that were weak.
God bless you, Sir. Terms of Service - Needle fluctuating under accelaration i notice is one of the diagnosis, what if on idle and revved a few times, that normal? Cookie Policy - The most I've seen in a big solid cam is 17". with NO vacumn hooked to carb and the carb port was plugged. March 19, 2019 Opening the idle screws more does not effect vacuum or quality but AF goes richer at 12:1. When I was a kid, my father and BJ taught me how to adjust a new or rebuilt carburetor by watching and listening to the engine. I said that I did a compression test and that all is at the right. Its high idleling and it has a code p0300 which is random misfire where should i start. A stock cam has will probably give higher readings. Once on the throttle 11 to 12 A/F, I am generally too rich.
I always read about how a big cam will give you lower vacuum numbers at idle. How much vacuum are you guys seeing at idle? I just lowered the idle as far down as I could get it without stalling. A good source for many is the vacuum line going to the transmission. Higher elevations may cause slightly lower readings. If the needle drops quickly and returns to a normal reading, a burnt or sticky valve is indicated. Need other technical information or engine specific advice? I like to push the hose on my vacuum gauge through the firewall/bulkhead (using an existing penetration) and connect it to a direct vacuum source like the manifold (more on this later) so I can watch my vacuum gauge as Im test driving the vehicle. The engine seems really cold blooded, and takes its sweet time to warm up. Has mild rv cam. Repeat on the other side if required. Kim. VP 5.7GSI wont start - good fuel pressure, good ecm, wiring - Page 53, Vac Visual: Quick Guide to Vacuum Gauge Readings - OnAllCylinders, Vac Visual: Quick Guide to Vacuum Gauge Readings | MEP Precision Racing, Can Low Compression Cause a Lean Engine Condition Like This? Should be able to get down to 750 with a cam like that (stock was 650). Do Not Sell My Personal Information -, By logging into your account, you agree to our. It was set to deliver 10* advance at part throttle above 8" of vacuum.
Next I would have never recommend such a large cam for street use not worth the hassel, I have a 292 cam and that has to be the dummiest thing one can do to a street engine. " It could be a vacuum leak or fuel drip, but check your valve lash. I have the solid roller version of the XE274 cam (236 @ .050) and am getting a solid 14" of vacuum at a 750 RPM idle. FFR 5353K, 408W, TKO 500, 2015 IRS w/ 315 gear, Breeze QA1 DA coilovers front and rear, APE hardtop, Forte front swaybar. It takes a 10 minutes to get the vacuum up to at least 15. Check the simple (inexpensive) things first like your pcv and breather to ensure they're not pulling oil before you suspect a port leak in the lifter valley. Not a good cam to start with, especially with only 9-1 compression. As stated, a stock engine should pull 17-21 In/Hg of vacuum at idle. Hello,
I have a vacuum gauge and A/F meter in my dash so I see these readings all the time. A full-blooded Native American Indian, hed often climb up after me into an engine bay (he was only five feet tall) to do stuff and explain what he was doing and why he was doing it. hallo mijn vacuum meter meet een snelle trilling boven de 20 inch Is this normal for a cam with an intake duration of 230 degrees and a lift of .48 inches? and vacuum circuit, HELP! The cool thing about using a vacuum gauge to diagnose engine problems is that different engine problems show themselves by vacuum readings in different ranges. Common causes of steady low reading are blowby due to worn piston rings or possibly late ignition or valve timing. You likely have a restriction somewhere within your exhaust system or a damage exhaust component. Make sure any ports or fittings that are supposed to be plugged are plugged properly. 17" isn't too bad, but there are some things to check. Years ago, my fathers main mechanic at the Chevron station, Billy Jeff BJ gave me a vacuum gauge as a birthday present. lift .673/.648, @.020 286/286, @.050 250/254 lobe at 107 centerline at 105. It is definitely not a stock cam. Using Engine Vacuum to Diagnose Performance Issues, 15-18 /Hg and holding steady the timing is retarded too much; advance, holding steady at 10-15 /Hg indicates valve mechanical timing issues, the, very low but steady readings of 5-10 In/Hg are indicative of a leaking. What can this be? Carb Size Street Car - Advantage of QF 780 cfm over 735 cfm? Needle steady and increases at acceleration. I agree to receive emails from the site. A couple of years later I realized that I got 20 deg of advance at full vacuum. To confirm, youll need to perform a compression test. 340 degrees advertised. Come join the discussion about performance, production numbers, VIN decoders, modifications, troubleshooting, power adders, DIY tutorials, and more! Privacy Policy. As I did some serious homework Terms of Service - Gremlins in the Thermoquad ? Comp Cams Mother thumper cam for something that WORKS.. With that much duration and low vacuum, it is just a massive vacuum leak. Start the engine and listen for leaks in several locations around the engine bay. Solid roller lunati 51019 with a 1.7 shaft mount rocker setup, put cam at about 256/264 @.050, .650" lift. I have a rapid fuctuattion between 14 and 15. I haven't checked it so i dont know what its at. "What vacuum reading is okay with a lumpy cam? document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); Alcohol Injected All Alum 632 cid Race Engine, BLOCKS-BLOCKS-BLOCKS in Stock Ready to Ship, Everything You Need to START a Chevy Performance Connect & Cruise System (LS and LT Engines), What To Look For When Your Hot Rod or Restoration Doesnt Start, An LS3 Swapped 1992 Buick Roadmaster Estate Wagon Project: Part Five. If you notice the needle slowly fluctuating between four or five inches, chances are you have an ignition-related issue. Begin your engine check-up by making a thorough preliminary inspection. The swing on the gauge is usually anywhere from 10 to 22 inches of mercury, depending on the speed of the engine. JavaScript is disabled. Please tell me if thats the proper This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register. Yours may be missing or old. The following errors occurred with your submission, 1967 - 1972 F-100 & Larger F-Series Trucks, Lightning, Harley-Davidson F-150, Roush F-150 & Saleen F-150, Conventional (Bumper Pull) Towing; Travel Trailers & Pop-ups, Toy Hauler Towing; Fifth Wheel & Bumper Pull, Flatbed, Car, Boat, Utility, Horse & Misc.
For good power brakes you will need at least 14 to 16 of vacuum. I would say that you are not too lean.
Increasing the idle speed to 1000 gives another 1" and decreasing it to 800 drops another 1". What cam are you running? Thanks Tedster! Trick Flow 2.02 Heads For every 1,000 feet above sea level, you can expect the reading to be about one inch lower. Edelbrock Air Gap manifold Very interesting to a Chevrolet fanatic that probably could assemble Steve,you are correct the idle vac will come down some when he reduces the idle speed but a 650 rpm idle is for auto trans in gear/not when in paryk where ot would idle higher & many manual trans setups idle in the 750-800+ rpm range. Post it here! I tried connecting to manifold once and it was terrible. A little low on the scale but good..(a steady reading). I have about 13 deg vacuum at idle, and always seem to be 13.5 to 14 A/F. I know on my setup if it is too fat at idle and i lean it out, the map sensor will start showing more engine vacuum where the engine actually wants to idle with less fuel. No matter where you get your vacuum source, make sure its not ported. You should never scrimp on your vacuum gauge. Come join the discussion about restorations, builds, performance, modifications, classifieds, troubleshooting, maintenance, and more! Low quality gauges can leak internally and give unreliable readings. Its so valuable, in fact, that OnAllCylinders contributor Lori Sams put together thisvisual cheat sheet to help youunderstand common gauge readings. For example, if youre seeing vacuums readings at idle of: Fluctuations in vacuum with the engine idling at operating temperature are indicative of either an engine misfire or a problem with a valve. Carb tuning is part art and part science. We discuss MK4, GTM, 818, Type 65 coupe, roadsters, and more! Adjust the rockers, My dodge charger has a higher than normal reading on the vacuum gauge its obove 25. The engine seems really cold blooded, and takes its sweet time to warm up.
That is going in the rear window tomorrow! When diagnosing engine performance problems using vacuum, you must use a direct source of vacuum, such as the vacuum tap on most intake manifolds. He's done pretty much everything in the automotive aftermarket from gas station island attendant, parts counter, mechanic, and new and used sales. idles at 950-1050 rpm. You are using an out of date browser. The ballast wire drops the voltage down, but the reason for that is to reduce the current that flows through the primary ignition circuit. Idle is 9" vacuum at 1100rpm. Solved. But, I also wonder if a larger cam is also playing a role in the lower vacuum readings. Archive - You ought to be pig rich in gear at idle and Everytime you mildly take off. Terms of Service - Don't see another board for your problem? hello, sorry for my writing I am French, I have a pontiac firebird 2.8l manual transmission of 1988 and on my vacuum gauge I read 16 hg with the occasion very slight increase to 16.5 hg and after having all check all the ignition it turns out that all works well and with the good advance besides if I try to advance the ignition i have a misfire can someone have an idea? Since its hopefully a fine instrument, treat it properly.
Steady vacuum is good.
Mike Aguilar I put it on the dash above the speedo so I can see the fluctuations as Im driving and link them to the driving conditions under which they occurred. advance,didnt work for me,lots, Found my problem,long story short,took a long drive That mix.