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UtahSleeper
02-20-2015, 01:52 AM
So, I imagine the diagnostics will be similar for most motors, but this question is in regards to a st215 motor I have installed and running in a st165.

Up until today, the car started and seemed to drive fine. Today it doesn't want to rev. If you push the gas to the ground it tries to do die. I can feather it a little and get the revs between 2k and 3k.

Torque is telling me code P0135, IIRC, which is just o2 heater so shouldn't cause an issue. Torque also seems to give me a vacuum reading, so I dont imagine it would be the map sensor.

Any assistance is appreciated

MrWOT
02-20-2015, 01:59 AM
take out the upstream o2 and leave it out and see if it revs

UtahSleeper
02-20-2015, 03:57 AM
K, I will give that a try. Should I take it out or just unplug it from the harness?

Also other side notes.

FP is louder then I remember, but it does turn on. Having the Fp and B+ jumped does not change behavior.
Car is now taking longer to finally start and some times will idle really low after starting.
If I barely push the throttle(like a couple degrees) the motor will start climbing.

donteatbugs
02-20-2015, 02:07 PM
Id check fuel pressure. If you have a walbro pump the line in the tank can come loose and you will get some fuel but not enough to rev it up. It would also not show up in diagnostics.

4thgenceli
02-20-2015, 03:29 PM
I agree with Bugs. Sounds like you're having fuel delivery issues. Did you bypass the charcoal canister at all?

UtahSleeper
02-20-2015, 04:02 PM
Charcoal canister is not connected or even in the engine bay anymore.

I will start simple and replace the fuel filter as there may have been sludge in the tank and maybe the new filter is clogged up.

Also, in torque it seems that the ECU had readings for fuel. Not sure what exactly at this moment, but if it has pressure listed maybe that will make diagnosing a little easier.

Thanks for all the input so far.

UtahSleeper
02-20-2015, 04:03 PM
take out the upstream o2 and leave it out and see if it revs

I tried disconnecting the o2 from the ecu and it did not change the motors behavior.

Facime
02-21-2015, 01:30 AM
Id put money on a fuel pump failure. Making noise is no guaranty that its pushing fuel at a good enough pressure.

Your new exhaust system is completely catless right?

UtahSleeper
02-21-2015, 02:46 AM
Id put money on a fuel pump failure. Making noise is no guaranty that its pushing fuel at a good enough pressure.

Your new exhaust system is completely catless right?

Yes.

MrWOT
02-22-2015, 01:47 AM
I tried disconnecting the o2 from the ecu and it did not change the motors behavior.

I meant physically remove it from the exhaust. I was thinking it may have been a clogged cat.

UtahSleeper
02-22-2015, 05:54 AM
I meant physically remove it from the exhaust. I was thinking it may have been a clogged cat.

Ah, no cat to clog lol.

So, I used the FP to drain the tank today. It pumped out about 4 gallons. Took somewhere between 10 and 20 minutes. Seemed like it wasnt pumping very quick, almost as if I had started siphoning the gas out through non pump methods. Unless there are other ideaas I am going to start with the FP first, although if I can find a cheap fuel pressure gauge I may test it with that before dropping the tank.

Facime
02-22-2015, 07:20 AM
Volume is one thing, pressure is another.

UtahSleeper
02-22-2015, 08:36 AM
Volume is one thing, pressure is another.

How long would you say a good alltrac fuel pump should take to move 4 gallons of gas?

Facime
02-22-2015, 11:15 AM
I dont know. I think the tsrm gives a volume test proceedure, but again, my point is that a pump can move sufficient volume but fail to make any pressure. Fuel pressure is every bit as important in a fuel injected system as volume is.

Additionally, a cold pump might work ok and then within a few minutes or up to an hour or so later start to fail. I had a trans am that would run fine for for about 10 miles and then slowly I would have to use less and less pedal to limp home. Then let it cool off and it would start all over.