Running extremely lean at idle and boost??????

[Squid4life]

That is the ported intake from me, right? What intake gaskets were used? It sealed fine on that motor with 1007 hg's and the good large port felpro intake gasket... (1200? 1400? I forget...)

 

[diponyou]

yeah that is the one

the car is back at Nick's

He is going to check it out and see whats going on with it. Hopefully just something stupid.

 

[Squid4life]

I hope it is something simple. Usually is with these damn cars... Always something. Sorry to hear it is giving you fits brother.

 

[diponyou]

I hope it is something simple. Usually is with these damn cars... Always something. Sorry to hear it is giving you fits brother.

Yeah me too. It was running like a raped ape until the gaskets blew.

 

[Chuck Leeper]

Definitely possible

Currently at idle it read 20lbs of vacuum at idle

I swapped o2 sensors and its still running like ass


Here are my readings on my scanmaster
o2 millivolts bounce between 170-800 at idle
af-06
L8-35
bat 13.1
int-131
bl-121-129
clt-160
ats-143
r- 950-1025
tps-.46-.48
iac-53
cc-168-189

that was after driving around the block and in park. Both fuel pumps running constant. At 5psi-10psi the wideband reads between 16-18(which is pegging the gauge lean)

If the idle vac is 20", and the IAC is at 53, I'm questioning the theory that there's a massive intake manifold leak. Yes/no??

 

[20psiofevil]

If the idle vac is 20", and the IAC is at 53, I'm questioning the theory that there's a massive intake manifold leak. Yes/no??

Good point. 53% iac on my car is a good reading. Also when I had a minor leak the rpms were much higher and the spark retard was in full effect to bring rpm back down to desired which in turn caused the headers to glow red due to low timing. It really sounds like ignition to me.

 

[1fastcobra]

Ck the coil. I've gottin 2 brand new that have been bad rite out of the box ohm it

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[diponyou]

Ck the coil. I've gottin 2 brand new that have been bad rite out of the box ohm it

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While that definitely could be an option
Before the headgasket swap, the car(in my opinion) was running damn near perfect. No missing or other funny issues. I have an HD video I took with my gopro the day the headgasket went as a matter of fact. The thing ran smooth as a new car all the way to 25psi.

 

[diponyou]

On the way to Nicks house on Friday( I am lucky and live about 20min from him ) on the highway while attempting to cruise the car just bucks and spits and does not like to drive. I mean it is serious bucking, my head was rattled when I go to Nick's house.
The only way to keep it from bucking and spitting was to constantly keep the rpms going up and down. I would have to accelerate, then slow down, then accelerate....you get the idea.

 

[Squid4life]

Let me know what you find out brother...

 

[diponyou]

So we got the intake machined. Still has a really bad miss :/
Gonna swap another o2 in. Check plugs. clean the maf and verify fuel pressure.

Running out of ideas after that.

The heads got machined and a valve job, is there any possibilities that something could have gone wrong that would give me these symptoms?

 

[1fastcobra]

Maybe a bad chip !!!!

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[diponyou]

Do tt chips go bad randomly?
It was running great prior to headgasket swap.

UNder normal cruising it stutters and misses constantly.
With Mild acceleration it picks up very nice with no missing.
Once back to cruising it just misses and stutters
From a stop it hesitates for a second before it takes off.

The o2 mv vary between 58-800 while steady at 65mph around 2k rpms

The wideband was pretty much at 18:1 the entire drive home. It would get to 14-15:1 at 5psi or so. I never went past that.

 

[1fastcobra]

For me yes !!!!!My older tt chip has a miss at idle
When I put my pte in it does not miss at all


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[diponyou]

Weird. I will email erik and see what he has to say.

 

[delcowizzid]

unplug 1 injector at a time with it idling and see if you can find any cylinders that arnt firing properly

 

[diponyou]

got the car washed last night, that thing was beyond dirty.

Anyways
I havent had a chance to work on it this morning yet but I am going to try swapping out the o2 sensor with a denso. I have been using bosch ones from oreillys. I hope that is my problem lol.

I am going to do a bunch of the basics today as well and hope for the best.

 

[diponyou]

OK

Still running extremely lean

Brand new Denso o2 sensor
cleaned maf
set base fuel pressure to 55psi with vac line off

absolutely no change

I know it is running lean because at around 5-10psi the timing gets retarded 1.0-1.5


does anyone know what this green wire is for??


any other ideas???

 

[Squid4life]

That wire go to the coolant temp sensor? Crap, I can't remember... Don't believe it went to back of alt. IIRC, there was one wire to the coolant sensor for the ECM and another for the gauge.

 

[diponyou]

Ok so me and nick had another talk

He recommended that I ground the pumps to a better location via 10g wire. I did that and still no change.

Next thing I am going to do is see about getting a fuel pressure gauge with long hose to see what my fuel psi is doing while driving.


Would that green wire affect anything if it isnt grounded?