Gunk ValveMedic

i know this is a old thread but there was never anything posted on it. done a search but couldnt find anything. i seen this stuff in advance tonight and was wondering myself if any of you guys have tried it? im experiencing some higer rpm ping and its driving me crazy.

thanks

Five-oh, high RPM ping is generally fuel related IMHO.

I would pull codes (lookin for lean codes, amongst others).

Cleaning the MAF wires, checking fuel pressure when you hear pinging, etc are things I personally would look at.



Good luck.

HISSIN50 said:

Five-oh, high RPM ping is generally fuel related IMHO.

I would pull codes (lookin for lean codes, amongst others).

Cleaning the MAF wires, checking fuel pressure when you hear pinging, etc are things I personally would look at.



Good luck.

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the car seems to run rich. when the car is idling, i can smell strong scents of gas. when i hammer on it, black smoke comes out of the pipes. the car doesnt hesitate or fumble tho.

stock injectors, stock fp ( as far as i know ), stock pump, etc.

i would like to check my timing. what is it suppose to be?.....10 degrees?

fuel pressure is suppose to be?.....38psi?


i have a hypertech chip installed. could that have any effect on the fuel/timing?


thanks!

Not to sound like a DB but a catless midpipe can be pretty stinky. Just in case that's the cause of the fuel smell. Also, this time of year is just when EVAP system leaks start to show themselves. A rotted purge solenoid hose is the most common issue that I've seen.

Sometimes having a high demand (generally what high RPM is) fuel starvation issue can cause the EEC to flip out trying to richen things up. This can cause a richer than normal condition at idle till it learns what's going on.

That said, I'm not sure what a Hypertech chip does for folks (nor how yours was configured). I once inquired about one from a gent whom was sellin his and he wasnt real sure what it did. In your case, you might want to pull the chip to see if the issue goes away. Some chips are tantamount to advancing global spark.

When you pull codes, dont flip if you see a ROM error. It's likely from the chip.

Backing the timing down, as you suggested, is always a good place to start. Also, as I recall, there's a bit less timing under WOT than non-WOT conditions (atleast on non-chipped cars). Knowing this can sometimes help with diagnostics.

Stock timing is generally about 10*. Stock FP is 38-39 PSIG at simulated WOT (vac line removed and plugged, and 32-33 PSIG with the vac line attached. The sim'd spec for WOT doesnt do anything to check for ability to keep up with demand however. You gotta tape a gauge to the windshield or something along those lines to check that.

Good luck.