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Fried_Chicken
10-12-2019, 03:44 PM
The ZHP is whining; Random misfires, and some running too lean.

Only recent service: put in refurbished/clean fuel injectors.

Any idea? Quick google search tells me it’s vacuum leak problems:
https://www.youtube.com/watch?v=QiqUAF0zxCk

I forgot the exact code being thrown, but i’ll update that in due time.
ComradeNick
10-12-2019, 04:50 PM
The ZHP is whining; Random misfires, and some running too lean.

Only recent service: put in refurbished/clean fuel injectors.

Any idea? Quick google search tells me it’s vacuum leak problems:
https://www.youtube.com/watch?v=QiqUAF0zxCk

I forgot the exact code being thrown, but i’ll update that in due time.Either o2 sensors (unlikely) or there is a vacuum leak, generally at the lower intake boot. Smoke test to confirm.

Sent from my SM-G973U using Tapatalk
Fried_Chicken
10-12-2019, 07:38 PM
Either o2 sensors (unlikely) or there is a vacuum leak, generally at the lower intake boot. Smoke test to confirm.

Sent from my SM-G973U using Tapatalk

Will do!
Fried_Chicken
10-13-2019, 09:58 PM
Looked, couldn't find any leaks... for some reason I checked my oil cap, and it was only threaded with one of the little ears.
Put it on right, solved the problem!
SureShot434
05-15-2020, 10:37 AM
Looked, couldn't find any leaks... for some reason I checked my oil cap, and it was only threaded with one of the little ears.
Put it on right, solved the problem!

If you are pulling that much vacuum in your crankcase you may want to look at replacing you CCV at some point. I saw a video the other day where the guy had to use a lot of force just to pull his cap off. If you pull the cap off and the engine looses RPMs or dies then it is time to replace the CCV. Couldn't hurt to check it out.
GeorgeH
07-07-2020, 02:31 PM
If you are pulling that much vacuum in your crankcase you may want to look at replacing you CCV at some point. I saw a video the other day where the guy had to use a lot of force just to pull his cap off. If you pull the cap off and the engine looses RPMs or dies then it is time to replace the CCV. Couldn't hurt to check it out.

A loose cap will cause lean mixture faults. BUT your description on checking vacuum on the cap with running is spot on for a quick CCVV check.