Car will only start when TPS is unplugged.

BlownSix

Registered User
This is where I'm at now. It will only start when the TPS is unplugged and I give it some gas. Then, the idle will shoot up to approx 2500-3000 for a couple of seconds and then it'll come back down to about 1000. So I did a KOEO test and got these codes: 118, 122 (TPS was unplugged), and 113. When we plugged the TPS back in, the car sounded as if it had major misses and the idle shoots back up to 3000.

(Note: this is a new TPS. Also has a new IAC.)

The oil pressure sending gauge and the temperature gauges are not registering at all, but we tested the oil pressure with a mechanical gauge and I do have oil pressure.

The fan is always on no matter what the temp.

What is going on?
 
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The fan always on is a sign the EEC is running the car in limp mode, which pulls alot of spark and drives the fuel really rich. ECT sensor failure will cause this as will TPS being unplugged.

Fraser
 
Hmm...okay. But when the car is cold, I can get the car to start with the TPS plugged in, but once it's warm it won't start unless the TPS is unplugged.
 
Have you replaced the ECT sensor? Its the one thats on the pax side next to the oil filler. If that is not working right and sending the wrong info to the EEC, it can mess alot of things up in the way it runs. The worse thing is, it won't neccesarily cause a code to happen since the EEC will still think its in range.

Fraser
 
No I haven't replaced that.

When I measured the voltage across the TPS the ground to the bottom lead reads about 4V and ground to the top lead also reads 4V with the key on. Shouldn't one be 5V and one be nothing?
 
shorted TPS

This does happen. Sensor is bad. Replace and all is well, Car will not start with tps shorted.

Also, if ECT is shorted, will do the same thing.

Don
 
im with frit sounds like the ect sensor took a dump

also note that with the tps in failed state the isc locks at 55 duty cycle or so which will cause her to start when warm and idle high

she probably floods out when warm trying to crank her
 
*Solved*

Well, I'm a little embarrassed :eek:

We got a fantastic wiring diagram and started looking it over. Turned out that the three sensors that were throwing codes were on the same circuit. Okay, we start tracing the wire and what do we find? The plug that has that wire in it wasn't snapped in all the way. It APPEARED to be, but it just wasn't seated. Hah! Bolted everything back up, and the car started right up. Ran the codes to make sure and it got a pass code. OMG we're both so embarrassed. We really thought we'd checked all the connections/connectors/grounds/etc but apparently we missed one. We think it happened when we took off the shock cover (we were recharging the A/C). It must've bumped it just right or something.

We'll be returning the parts that we bought tomorrow lol. I was THIS CLOSE (holds thumb and pointer finger a cm apart) to saying screw it! :p

Thanks to everyone that gave their input!

I will be uploading this wiring diagram and see if it can be made a sticky or something so it can be easily found.
 
It was definitely the cheaper fix! Lol...anyway, it was the connector all the way to the left of the engine back up near the firewall (facing the car). Just make sure they're all snapped in.
 
Darn! I was hoping to pick up another nice cheap SC.

Glad you got it worked out. Finding a problem like this is almost as satisfying as...
 
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i think i read it on sccoa a few years ago or in the shop manual , that if you start the car 3 or 4 times and never go above 40 mph the fan will run continuous, and that seemed to happen to me once where the fan was running a lot , till i read that post then i understood , and it went away the next time i went over 40 mph
 
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