'96 Riviera S/C problems

Hey, I'm new to this site but I have owned a Riviera for the past two years with no problems.

But last week, after changing the oil and putting a new fuel filter on, I drove it across town and all of a sudden it started slowing down
and would not go past 45 mph. So I pulled into a parking lot and it stalled.

Long story short, I got it towed back to my house and if it decides to start, it sputters and stalls.

My roommate and I have replaced some broken vacuum lines, replaced the thermostat, the battery is fine, checked some codes.

The codes we got were: P0113 (IAT sensor 1 circuit high input)
P0300 (Random/Multiple cylinder misfire)
P1441 (Manufacturer control aux. Emission controls)


We are at a loss now.

I will upload a video or sound clip as soon as I can.


Any help will be appreciated.

Thanks

This sounds stupid, but is your fuel filter leaking on either end? also maybe some other parts of the fuel line were brittle and finally broke a bit during the installation.

Good idea checking the codes. Probably a combination of problems. The P0113 could be a bad sensor in the air filter box, or the connector could be unplugged or a wire broken. It shouldn't cause your car to stall out like that, but that's usually what sets the P0113 code. When it happened to me, it caused the AC to run badly, so if yours isn't working right, that's probably why.

Can fix the P0113 for $20-30.

RidzRiv wrote:

This sounds stupid, but is your fuel filter leaking on either end? also maybe some other parts of the fuel line were brittle and finally broke a bit during the installation.

The fuel filter isn't leaking, but is the any way to check to see if something got stuck in the line? :/

check your fuel pressure with the key on. Then watch the FP while you are trying to start it. Tell us what you get.

What make fuel filter?

Did maybe some of those vac line replacements (there are not many vac lines) get misrouted (but some of the connections are close-by each other)

deekster_caddy wrote:

check your fuel pressure with the key on. Then watch the FP while you are trying to start it. Tell us what you get.

will do when I get home

albertj wrote:

What make fuel filter?

Did maybe some of those vac line replacements (there are not many vac lines) get misrouted (but some of the connections are close-by each other)

The filter is a cheap one from autozone. As for the vacuum lines we replaced them one by one......to make sure there was no mix up lol

i do know its hard to diagnose problems with out being there or able to see/hear it......i do appreciate the help everyone

AA wrote:

Good idea checking the codes. Probably a combination of problems. The P0113 could be a bad sensor in the air filter box, or the connector could be unplugged or a wire broken. It shouldn't cause your car to stall out like that, but that's usually what sets the P0113 code. When it happened to me, it caused the AC to run badly, so if yours isn't working right, that's probably why.

Can fix the P0113 for $20-30.

the AC has never worked but i don't mind right now, i just got a job so i just need it to run lol

but if that sensor is bad could that mess up the air/fuel mixture?

That sensor could be the reason your AC doesn't work, or at least one of the reasons. IAT mainly controls ignition timing, but I suppose it could affect the A/F mix, too.

hmmmm....we'll have to check that out then

is there any visual way to check the sensor?......probably not but i have to ask lol

Yes, you can test the sensor with an ohmmeter. It should read about 3000 ohms at ~80ºF. It won't be exact, because the reading will change depending on temperature. But it shouldn't say 0 ohms (shorted) or open circuit.Even very hot it shouldn't be over 100k ohms.

ahhh ok I'll check that when i get home

to me the code to focus on is the P0300.

Do you have access to a scan gauge?
Can you monitor 02 sensor values, MAF readings and LTFT?

Mr.Riviera wrote:

to me the code to focus on is the P0300.

Do you have access to a scan gauge?
Can you monitor 02 sensor values, MAF readings and LTFT?

uhhh no I don't .......but i have seen it before but never knew what it meant, what is LTFT?

LTFT = Long Term Fuel Trims

when you say the car would not go past 45mph, were you revving it up and the car just wouldnt move or were the rpms not rising as you were giving it gas?

The rpms were and are rising when I hit the gas, but now when i do manage to get it started it won't rev past 4k

If you're in park, that's the rev limiter doing its job.

ahhh ok that makes sense lol

Ok well when it happen it didn't want to go over 45 then it stop and didn't want to go over 25 then i tried to think what it would be and sometimes it would start and stay on then other times it would not so i can think what it will be.

vegasdgk wrote:

The rpms were and are rising when I hit the gas, but now when i do manage to get it started it won't rev past 4k

A little detail - the 3800 is *not* a high revving engine. If you want something that will rev high (many 4 cyl engines) this is not the engine for you. Has to do with the cam lift and angles needed to produce lots of low end torque so the car can cruise at 55 - 65 mph at revs below 2000.

Albertj

i do understand that....i love the car, it has potential but my roommate has a 95 z28 camaro, which obviously is a bigger motor and said that it doesnt seem right.
i rarely check the rpms when it was working :/ so I'm not sure what the normal rpm is.

The random misfire code seems to hint at possibly a spark plug wire arcing somewhere or something else which could cause legitimate performance issues. I'm not sure what the IAT code could cause... they are so cheap it's worth seeing if you can get a new one or low mileage replacement from Morad Parts Company online. Stupid question.. how doesn't your air filter look? I had serious performance loss in an older car when a POS mouse made a nest in the air cleaner. The car ran like shit and I couldn't do much past 50mph. Worth a shot I guess..

The air filter is clean, we changed it with the oil and fuel filter, (i should have mentioned the, sorry lol)

but when i get some money (lol) i will replace the IAT.

one of my friends was over earlier and said "it sounds like you aren't getting any fuel"

so like I said, i will get a video or sound clip posted asap