odd issue when car is warm

[obracer12]

b16b
s80 transmission
No codes, at all

new:
wires
plugs
cap
rotor
ICM
oil change
coolant change/ fully bled


Checked:
fuel pressure
ICM ( thus the replacement, it was throwing below standard voltage on 2 pins and had 0 conductive grease on it)



The car drives and acts fine when cold (over night) , can make it the 17-20 mile drive to work with no problem, standard acceleration, everything.

When the car warms up, it will idle fine...

idle drops to 5-700 , then at cruising around 3krpm, the rpms will jump, the car will sputter/buck and then rpms will drop to 0 and the car dies.

My next thought would be the TPS through the crude method of just unplugging it while at rough idle and it normalizes to ~800-1k

Other than that I'm at a loss....

Going to replace the tps tomorrow and drive around town and see what happens

Any other thoughts as to what it might be should this not work?
I was thinking cooling system related next.

 

[RonJ]

Check whether unplugging the primary O2 sensor eliminates the problem.

CEL work?

What were the fuel pressure readings?

 

[obracer12]

I'll try the O2 sensor when it happens next.

Cel functions properly, instant code when I unplug the tps at idle

As for psi I'm not sure, did the quick and dirty test on the side of the road

 

[RonJ]

As for psi I'm not sure, did the quick and dirty test on the side of the road

Post fuel pressure numbers at idle with and without FPR vacuum hose disconnected/plugged.

 

[obracer12]

Assuming the pressure is fine, which would be the most likely culprit? O2 or tps ?

 

[obracer12]

Update, tested tps
.51v with butterfly closed
4.63v at wot

Will .4 v at wot be the issue?

second update:

Duplicated the failure
opp temp
idle bogs
car dies
no start condition until cool


Unplugged O2 sensor and tried to duplicate the failure and could not...

Still idled low and threw a CEL

Not 100% that it's the O2 and I know my IACV needs to be cleaned.

 

[RonJ]

Your TPS readings are fine.

But keep in mind that intermittent problems are the most difficult to diagnose because any diagnostic tests are only meaningful when the problem is happening.

For example, when the problem is happening, if you unplug the O2 sensor and the problem stops, then the O2 sensor is almost surely the problem and should be replaced.

The same idea applies to fuel pressure. If you get out of spec pressure readings when the problem is happening, then there's a fuel system problem.

Was your ignition system tune up done with quality parts? Have you Ohm tested the coil?

Have you tried adding some Seafoam to the gas tank?

Have you tried buying gas at a different station?

 

[obracer12]

You're awesome


I have not tested the coil yet but it's next

I get gas from a reputable station but never the same ( Sunoco, wawa, shell) never a dive station

It is definitely a temperature related failure, when the car is at temp then boom issues

Tune up was done with dura last cap and wires, ngk plugs, kn filter, icm is NEC

 

[obracer12]

Drive the car with the o2 unplugged, duplicated the failure...

 

[obracer12]

Starting to suspect the coil... Unplugged maf, no start... Unplugged o2 no change, tps tested fine and fuel pump primes and there is pressure, ICM replaced...

Heat to expansion fault within the coil sound plausible?

Currently on the side if the road 50% of the way to work

Edit:
Picked up a coil, going to road side swap it and drive to a hockey game... let's see what happens

 

[obracer12]

^ really?

Eliminated almost everything but the coil and a fuel delivery issue, Rail and injectors.. Possible but not probable ecu problem...

You're good, but take a few steps off your high horse

 

[Failsafe88]

^ really?

Eliminated almost everything but the coil and a fuel delivery issue, Rail and injectors.. Possible but not probable ecu problem...

You're good, but take a few steps off your high horse

Lol you missed the thread yesterday....

 

[obracer12]

Which one?

 

[Failsafe88]

His f**k everything and everyone thread

 

[obracer12]

is he going to kill himself?

I see that thread was removed btw.