ERV question???
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ERV question???
Hopefully someone can answer this. I am getting a little bit of vacume at the EGR when the engine is still cold. I have considered putting a restrictor plate on, but would rather find the source of the problem and fix it if nothing more that experience and the principle of fixing the problem. This last weekend I put a vacume pump on the lower (intake) stem of the ERV and it did not hold vacume. I would think it should since it controls the vacume going to the EGR. If I am wrong I would appreciate some one letting me know so I can dig further.
Also I did the test in my Haynes manual for the MAF. It said to check voltage as vacume is applied. The reading I get is not nearly as high as the manual says it should be. When I apply vacume it goes way down. Not a smooth transition. When the truck is running and I pull the vacume hose off the truck just about dies. Again am I doing something wrong or is this a possible problem source.
92 F150 i6 2wd all original
K&N Filter w/ airbox wrapped
Thanks
Also I did the test in my Haynes manual for the MAF. It said to check voltage as vacume is applied. The reading I get is not nearly as high as the manual says it should be. When I apply vacume it goes way down. Not a smooth transition. When the truck is running and I pull the vacume hose off the truck just about dies. Again am I doing something wrong or is this a possible problem source.
92 F150 i6 2wd all original
K&N Filter w/ airbox wrapped
Thanks
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From: redding U.S.A.
Its normal for the engine to stumble, and almost stall when you unplug the MAP (that is what you meant right? )
It should stumble and cough like mad, then jump back up, and idle really high with it unpluged. This is sort of a "safe mode" that it does.
How does the truck run? I would think with the MAP diagnosing bad, it would run like crap.
It should stumble and cough like mad, then jump back up, and idle really high with it unpluged. This is sort of a "safe mode" that it does.
How does the truck run? I would think with the MAP diagnosing bad, it would run like crap.
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Sorry I meant MAP. It runs good with the green vac line off the EGR and plugged. It was bucking or missing at around 2,000 RPM (35-40 mph). I just feel better if I solve the problem of having vacume to the EGR all the time. It is not a lot of vac. but can feel it when I pull the green vac line off the EGR. Didn't register much when I hooked it up to the vac pump. When I pulled the line off the MAP it stumbled pretty good. Didn't leave it off very long. The main thing is the ERV below the EGR. Should it hold a vacume when supplying it to the vac source end. I would think that with having vac there all the time it should hold until the ERV opened the gate to the EGR.
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From: redding U.S.A.
I'm not familiar with how the EVR is regulated/composed, so i can't really help you there.
The theory going around here is that the large EGR system creates a lean condition that results in power loss and stumbling at around the torque peak, which should mirror the air intake flow/velocity.
Unless you could flatten out the A/F ratio from the EGR created lean condition, you're probably not going to find much luck.
Some 300ers have had this symptom from 0 miles. Just a tick of the 300 i guess.
The theory going around here is that the large EGR system creates a lean condition that results in power loss and stumbling at around the torque peak, which should mirror the air intake flow/velocity.
Unless you could flatten out the A/F ratio from the EGR created lean condition, you're probably not going to find much luck.
Some 300ers have had this symptom from 0 miles. Just a tick of the 300 i guess.
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From: ricelake wi
I have heard that a bad EGR can create the lean condition by having an internal vac leak thus letting it suck air sending the air back to the intake causing the problem replace the EGR and fix the lean condition as for VAC at the EGR constantly there should be vac there all the time or it would act like a potato in the exhaust check to see if the vac increases when you increase rpm it should , it should have most vac at w.o.t. thus opening the EGR all the way
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dbarracuda
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