This one's pretty important. I need to make a long trip on very short notice, over 600 miles round trip, leaving ASAP in the next day or two if possible.
I'll be driving a 1998 Cavalier, 2.2 3 speed auto, 140k miles. It doesn't get quite the fuel economy I would like, misses a bit when cold, and a few times it has had a problem starting where it wants to die immediately. I was able to start it by trying 3-6 times, and then it would run fine. It has had the crank position sensor replaced lately (before I bought it). I'm getting the following codes:
· P0113 Intake air temp circuit high
· P0122 Throttle Position (TP) Sensor Circuit Low Voltage
I've read that the TPS code is actually the pedal position sensor, although there is a separate set of pedal sensor codes in reference manuals. I've also found several instances on the internet of people having the same 2 codes simultaneously (more than a coincidence, I think) on vehicles ranging from Honda 4 cyls to Ford and Dodge trucks - usually with no solution listed or some cause other than the sensors such as the intake manifold gasket. I don't know if I'll have time to test the sensor ranges myself.
I'd like to get this figured out and maybe fixed before I leave, especially if anything is dangerous. I don't especially like the idea of going on a long highway trip with a faulty throttle or pedal sensor! This CEL code also disables the cruise control. 600+ miles is a lot easier with better fuel economy and functional cruise
Any help or suggestions are welcome. Thanks! -Jason
My guess those two sensors are wornout, Or I would take a look at the connection plugs make sure they are connected tight, And wiring harnesses are in good shape,
This reeks of a grounding problem, or maybe your 5v line isn't really 5v. I'm pretty sure the ECU takes these signals in reference to a ground somewhere. If the sensor ground and ECU ground are off, you'll get the error. If it were only one code, I'd look at the sensor first, but they can't both be failing simultaneously, can they?
2002 Cavalier 2200 5spd
I can help you out a lot here.
"
I've read that the TPS code is actually the pedal position sensor, although there is a separate set of pedal sensor codes in reference manuals."
I think your misunderstanding this actually. The TPS is mounted to the throttle body. When you hit the gas it moves it open more, therefore increasing sensor voltage. So like is .9V, 30mph is like 1.3V, WOT is 4.9V.
So if the sensor is giving a low voltage. It is either a loose connection. Of the sensor is giving out say 1.5V when it should be 1.9V. The computer also is watching this sensor all the time as it is one of the five majors, so it can clacualte looking at the MAP, where the TPS should be. If it seems it ias right more than once it will set a code.
The IAT is another 5V sensor. Again a loose connection first thing to look at. Since this sensor is normally like the ECT, negative temp coefficent. Temp up, resistance down. So if it giving out a high voltage. Most likely the sensor failed overnight. The reason I say this is the computer looks at IAT temp from the last few start ups, if it sees 72F, 87F, 91F, it doesnt care, it actually might be higher temps because underhood temps hit about 130F in the summer. Anyways if the next day it saw -40 ( which is what the sensors default is, same as the ECT). It says whoa something is not right here, setting a code.
Anyways normally I would whip out a scan tool and test these, but since its an emergency for you. I recommed buying new parts. And some Autozone crap, but AC Delco, GM parts. They are exactly what came with your car, not some knock off one sensor fits all BS like AZ sells.
- 2004 Cavalier - 124k, owned since new
I just realized something else.
You said it dies on cold start up. Colder air is more dense, which means more air, which means more fual. If the sensor is giving to high of reading, the PCM will pulse the injectors less. So possibly it isnt getting enough fuel, but after a few times it is because the cylinder temps have increased slighty after you cranking it five times.
Bad IAT not doubt.
- 2004 Cavalier - 124k, owned since new
Rob S wrote:I can help you out a lot here.
"I've read that the TPS code is actually the pedal position sensor, although there is a separate set of pedal sensor codes in reference manuals."
I think your misunderstanding this actually. The TPS is mounted to the throttle body. When you hit the gas it moves it open more, therefore increasing sensor voltage. So like is .9V, 30mph is like 1.3V, WOT is 4.9V.
Yes, I know how it works, but I definitely read and even heard from one guy in person that when it says code 122, it actually means PSS not TPS. Given that there are PPS codes, I think the guy didn't know what he was talking about
Solid Snake wrote:This reeks of a grounding problem, or maybe your 5v line isn't really 5v.
This is what I'm thinking since both codes seemed to start at the same time, and because other people have also gotten these exact 2 codes at the same time.
Thanks for the ideas everyone, I'm sure it will help me troubleshoot and fix the problem(s). For now though, it seems like it will take less time for me to get the Fiero reassembled and drive it instead. It's so much more reliable and easier to work on than a Cavalier! Roomier and more comfortable on long trips too
