IAC and different cams

[bsdlinux]

My doesn't want to idle at all around 20 IAC counts. I have a 218/218 Comp Cam. Anyone have a cam similisr to mine that idles at stock specs. The car likes to idle at about 1200.

TPS is at 44

 

[bsdlinux]

Bump??

 

[Richard Inglett]

Originally posted by bsdlinux
My doesn't want to idle at all around 20 IAC counts. I have a 218/218 Comp Cam. Anyone have a cam similisr to mine that idles at stock specs. The car likes to idle at about 1200.

TPS is at 44

When I was still using Comps 218, all three had decent idle in the 850 to 900 rpm range. Please advise what size injectors you are running and what your static fuel pressure is. Also advise if you are running a stock MAF. That 1200 rpm sounds a bit high.

 

[bsdlinux]

Re: Re: IAC and different cams

Originally posted by Richard Inglett
When I was still using Comps 218, all three had decent idle in the 850 to 900 rpm range. Please advise what size injectors you are running and what your static fuel pressure is. Also advise if you are running a stock MAF. That 1200 rpm sounds a bit high.

Thanks for the reply Richard. I have:

009 injectors
40 psi with line off
Stock MAF 3-6
TPS 44
O2s varying as they should


I did the tap test on the MAF, but I understand that is not always conclusive. I figured that the cam should still be small enough not affect the stock idle parameters. I just wanted to make sure before I start looking into all of the little details. The IAC is new and the TPS is new. I had the PCV shoving oil in the plenum as most seem to. Fixed that problem, but it is possible that the new IAC might still be shot even after I cleaned the TB. etc...( oil was in plenum after a new IAC was installed )
Hell it could be the MAF, I have another one on my other car I can try.

Doesn't matter how good of a mechanic you have been or are, these cars can humble the best of them.

 

[Richard Inglett]

Don't think it's your MAF. In my case, they have either worked or failed completely. However, cannot say the same thing about aftermarket sensors. They cause all kinds of strange problems.

Is it correct to say that this is a new cam installation and that the cam was the only change; or, that idle problems are recent developement?

Before making the next statement, please let me clarify that chips have come a long way since my experience. But, the 009's combined with your chip might not be helping your idle manners.

Recommend the following:

- AC PCV (does make a difference).
- Clean air filter.
- Check injector wires (especially around the EGR).
- Verify that EGR is not stuck.
- Try lower (38 psig) and higher (42 psig) fuel pressure. If lower pressure helps, don't forget to lower your boost.
- If applicable, try GM MAF.
- Try another chip. Had very nice idle with Ramcharges chip, 55's and stock MAF.
- Do professional injector cleaning.
- If available, different (50's) injectors and chip.
- Confirm that cam was degreed. I had one that was off 6 degrees.
- If frustrated and just for fun, set TPS to .38 with valve completely closed then set TPS to .44 with the adjusting screw. I know this sounds weird but it seems that the 218 likes a little more air. Might help.

Good luck,
Richard

 

[bsdlinux]

Richard,

Thanks for the response.

I have Eric Marshall doing a new chip for me. He has also mentioned the 009s idling issues as well and thinks he might have a fix for that.
We are working on the tip-in stumble issue. He has some code in there for the MAF readings.

The engine is a 6k rebuild. Good quality rebuild from the previous owner. I am just trying to get the bugs out before I put real gas and or propane, alchy, etc to really go fast.

Yes the idle has seem to get worse in last couple of weeks. I have taken the car off the road until I find out what the deal is. The idle basically sucks if you put it to specs. I did find the MAT sensor reading 72 all of time after I found a MALF code for low temp. Cleaned the connections and it seem to do better and read correctly, but still idles like crap. I am going to take the IAC out completely so I can inspect it.

After fooling with car yesterday, it seems I was able to lean it out a bit so it is not pig rich at idle anymore.

The only reason I was thinking MAF; is that I did a WOT blast yesterday and MAF reading did not get above 180. This was at 15 psi boost at 4900 RPM.

Go figure...I'll know more when the new chip gets here.

I like the idea about .38 on the TPS and adjust it to .44. Can I assume some first hand experience here??

Would love to go to 50s right now!! You have some??

 

[Richard Inglett]

Sounds Promising

bsdlinux,

Regarding your statement:

"I like the idea about .38 on the TPS and adjust it to .44. Can I assume some first hand experience here??"

Yep. Afraid so.

Have one more question for you, what size turbo are you running?

Finally, don't have any 50's. After trying the 009's, jumped straight to the 55's. With the available refined programming, 50's are a nice option. Save up.

P.S. Sounds like the bugs will be gone in about a week.

Best regards,
Richard

 

[bsdlinux]

Re: Sounds Promising

Have one more question for you, what size turbo are you running?

TA-61, Turbonetics Deltagate with in car boost control, ATR 3' downpipe, with test pipe and dump. Stock IC, Stock TB, Port matched intake. Fully Ported and Polished heads,
Blah....blah...blah...

Later

Gary