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blue62 · 08-09-2021, 10:23 AM

Yes it looks from the oil dirt residue that you have some minor vacuum leaks.
I do not think they are the problem. They do need fixed though for optimum performance.
The fact that you can drive the car at any speed or RPM as long as you hold the throttle steady then only get the judder when giving it more gas is not how a typical vacuum leak responds at higher RPM's

So it acts more like fuel delivery issues. either low pressure or low volume.
if it was injectors fouled or not working correctly I would expect the engine to run rough at all RPM
Yours will run smooth as long as you don't demand fuel under load. So if it is a fuel problem I think it would be a pressure or volume issue.

Another possibility is a restricted exhaust.
Both low vacuum and your judder could be caused by a restricted exhaust.

You can test for restricted exhaust with the vacuum gauge.
PITA I know
With engine at operating temp hook up the gauge and hold your RPM as evenly as you can at 2000 RPM for a minute to minute and a half.
watch the needle if it slowly drops from the initial reading you have an exhaust restriction. like plugged cats. or bent exhaust or something not allowing exhaust out.
If exhaust can't get out fuel/air can't get in.

'

08-09-2021, 10:23 AM	#6
blue62 Registered User Join Date: Aug 2018 Location: Woodland Wa Posts: 1,309	Yes it looks from the oil dirt residue that you have some minor vacuum leaks. I do not think they are the problem. They do need fixed though for optimum performance. The fact that you can drive the car at any speed or RPM as long as you hold the throttle steady then only get the judder when giving it more gas is not how a typical vacuum leak responds at higher RPM's So it acts more like fuel delivery issues. either low pressure or low volume. if it was injectors fouled or not working correctly I would expect the engine to run rough at all RPM Yours will run smooth as long as you don't demand fuel under load. So if it is a fuel problem I think it would be a pressure or volume issue. Another possibility is a restricted exhaust. Both low vacuum and your judder could be caused by a restricted exhaust. You can test for restricted exhaust with the vacuum gauge. PITA I know With engine at operating temp hook up the gauge and hold your RPM as evenly as you can at 2000 RPM for a minute to minute and a half. watch the needle if it slowly drops from the initial reading you have an exhaust restriction. like plugged cats. or bent exhaust or something not allowing exhaust out. If exhaust can't get out fuel/air can't get in. ' Last edited by blue62; 08-09-2021 at 10:37 AM.