Car seems to pull harder at 1/2 throttle than WOT

[Whizbang]

as the titles states, the car pulls much harder at 1/2 ish throttle than at wide open throttle which leads me to think the car is pulling timing for some reason or that the oil throwing turbo just cant put out at WOT anymore. Thoughts?

[djmtsu]

Is it loading up (pig rich)?

Do you have a wideband?

[Whizbang]

i do not. the car is stock less a DP and a FCD and the emissions removal. I run about 8lbs.

[djmtsu]

Hmm, similar set up to me.

Cat-back?
Secondaries leaking (too much fuel)?
Clogged catalytic converter?

I can maybe see the timing retarding, but not that much.

[Whizbang]

i have no cats, and ist just a straight pipe back from the turbo.

can't verify on the injectors with the too much fuel, but i wouldn't rule it out.

[Whizbang]

im curious if the turbo is just blowing alot of oil and its killing the quality of the combustion

[Apex944]

I have the same issue with my T2, oil blowing turbocharger and all.

Stock fuel system other than a walbro, gutted cats but stock dual exhaust and a custom 3 inch TID setup.

I hit about a 10.6 :1 air/fuel ratio at WOT which makes the car feel like it doesn't have anything to put out. But if I go 1/2 - 3/4 throttle it'll stay between a mid 11 and 12.3 :1 air/fuel ratio and I can feel the power.

I'm using an Innovate LM-1 with LC-1 gauge setup and analog out for my ECU to read an O2 signal so it can go into closed loop.

Anyway that you can get ahold of a wideband setup?

I'm thinking your having the same issue as I am with running too rich of mixture at WOT and it's killing the power. The oil blowing turbo isn't helping either haha.

[Whizbang]

hmm, i would be curious as to WHY i am putting out that much fuel. It HAS to be the injectors if that is the case. I may just wait a little bit since i want to get the Rtek 2.1 and get two new 720cc secondaries and then second the secondaries i was out for a cleaning at witchhunter and use them for the primaries when they get back.

[Whizbang]

Originally Posted by Apex944

Anyway that you can get ahold of a wideband setup?

My one thought would be that the carbon from the excessive oil burner might be harsh on the wide band sensor. Ill probably invest in one over the winter once i get work lined up in colorado.

[Whizbang]

my car is also now having a surging idle....

[djmtsu]

Vacuum leak.

[Whizbang]

i have NO idea where the leak could coming from though. I need to take the manifold off and see what might be left to leak.

i have all the emissions removed and the BAC. There is one thing that comes to mind i need to check. The ports that are unused on the UIM are capped securely, ive checked several times. Other than that, i would have to look.

[Whizbang]

another thought, could the TPS be bad since that is also reportedly another cause of a sugring idle? if i have the intercooler off i might as well throw a voltmeter on it to check.

[djmtsu]

I had a problem similar to this when I got back from DGRR 2K7. I developed a leak at the rear of the UIM gasket. Then when I took it off, I found out my injector bleed vacuum caps had dried out and cracked, causing a few of them to actually fall off.

Replaced all that, new gasket (thanks Landers) with a thin layer of sealant, new vac caps and good to go! No problems since.

I can't believe I didn't think of it sooner. I'm getting old.

[djmtsu]

Originally Posted by Low Impedance

another thought, could the TPS be bad since that is also reportedly another cause of a sugring idle? if i have the intercooler off i might as well throw a voltmeter on it to check.

Check for dead spots, but I am still going for vacuum/boost leak.