TII: Judgement Day

Okay, an 88 TII here.

The error codes I'm receiving is a bad oxygen sensor, air intake temperature sensor, and water thermo.

I'm not sure if the TPS is bad too, but it didn't come out as being bad.

Anyways, The car will start but shuts off at 1500 rpms... it smeels EXTREMELY rich. Would those error codes have anything to do with the way the car is running? Also I figured that with a broken TPS, the ECU will assume 100% throttle, right? If so, could this be leading to how rich it is?

playdeadva

judge,

Here in VA Beach...looking at buying my first s5 90 GLX. Are there any tuners or mechanics in the area?

The guy wants 3800 for a stock 90 GLX. Really wanted a TII.

Sorry I dont have a remedy for your problem...

jono20

The ECU will use all three of those sensors to fine tune the fuel deliver to the engine, id say YES, they do have a lot to do with how the car is running. replace them or fix them and see what happens.

I dont think the TPS defaults to WOT, but I couldnt tell you for sure

TII: Judgement Day

Thanks for your knowledge you provided.

Anyone else have any input? My car has been sitting still for over 4 months, because I've been too busy to figure the **** out.


playdeadva, IM me on AIM: qwiksillva. I'll try to help you with some local tuners around the 757 area and other info.

NZConvertible

You need to be reading the FSM. Fault code trouble-shooting is covered in detail.

A faulty O2 sensor is ignored and has little to do with running the engine anyway.

You don't say which air temp sensor code you get (there are two different sensors), but both default to values that will let the engine run okay (20degC/68degF).

The coolant thermosensor defaults to a warm reading (80degC/176degF), so the engine will run poorly when cold because it's not getting enough fuel but okay once warmed up.

The TPS does default to a 25-100% throttle opening (narrow range sensor remember) but this has no effect on fuelling. Note that a TPS that's not set right will not create an error code, but it will effect the engine's running. As long as it's plugged in and the ECU sees voltages in the right range you won't see an error code.

I can't see how any of these sensors could cause the symptoms you describe, but you should still follow the trouble-shooting procedures in the FSM (page 4B-24 onwards) to eliminate them as potential causes and clear the codes.

Have you checked the ignition system? A bad plug or lead would result in poor running and excess fuel in the exhaust.

HAILERS

Make sure the plugs are on the items listed. If they are on, then go to the ECU and see if their outputs conform to the listing in the FSM. There's a section called Control Unit that lists the output/inputs of all the devices.

That won't fix a engine that starts and runs up to 1500 and dies. You didn't say if there was any way you could keep the engine running. Is the car driveable? Or does it just die as you said and will only run up to 1500 and die and that's it?

bradenscreed

mine threw 6 different codes at me at once, i swapped out the ECU and tuned the TPS and now runs like a champ. just my imput.

TII: Judgement Day

Very informative guys thanks a lot.

The car is by no means driveable. It shuts off at 1500rpms. I just recently swapped out the ECU in March of this year. As for my ignition system, I recently replaced the leads and plugs. I tested my coils and they are doing fine. I did some "super grounding" as well.

This car is very hard to figure out. It has a curse, I tell you. Should I make an attempt in swapping out the ECU again? I must admit that ever since I've put another used N333 ECU is the car, it was better than before, but everything progressively got worse again. Just for everyone's information, the car lead to a progressive death in late April. It got worse and worse as time went along.

Lots of bogging, backfiring, hesitation, and boucy idles (vacuum system is sealed, so I know it's not that.

If anyone has experienced somethign similar to this slow death, please let me know. I would like to hear some experiences on how it turned out.

Keep educating me guys.

HAILERS

If you install that fuel pump check connector (yellow, two socket near the afm) and turn the key to ON, and sit there listening, do you hear the fuel pump running and the fuel gong thru the fuel rails back into the fuel tank? Sort of a splahing gurggling sound as it goes back into the tank?


Is your afm's electrical plug on good? Pull it off and then reinstall it and try starting the engine. The plug pulls straight off. Do not unscrew any screws to get it off.

Is the brake booster vacuum line on good? Its at the rear of the intake manifold. There is a half inch wide metal line that runs along the firewall from the booster to about centerline of the bulkhead and from there it connects to a rubber vacuum hose on the intake manifold.

Take a look at the duct that comes off the turbo and feeds the intercooler. Make sure the two small hose connected to it are on. One for the bac and one for the blow off valve(air bypass valve).

Make sure the duct from the afm is connected to the turbo at the turbo inlet. Make sure its clamp at the turbo is on good and the duct isn't split intwo there.

TII: Judgement Day

I'll check the fuel pump & update on that.

AFM electrical plug is fine. Checked.

Brake booster line is brand new and sealed perfectly.

I have removes my emissions on my car.

Yeah, the AFM is at the turbo inlet. It's always been there. Everythings very tight and sealed. No brittles hoses or anything. All remaining vacuum lines and hoses on the car are brand new as well. I even have brand new fuel hoses (not lines though).

Anything else? I'll check the fuel pump very soon and update on it.

RX7FROMCAL

mine was doing the same thing , but at 2500 rpms. it wasnt getting enough fuel, mine was only pushing out 5 lbs , when it should have been at 40 or above. now it revs great, i just need to get my idle down now , lol