1989 GTU problems

[GTU89]

Ok, I got a 89' GTU very recently, First the idle was really low (650-780rpms) sometimes below 650, it would try to stall then, and now today its pretty high (1280-1390rpms) same weather, hasnt been driven in about 4 days. but its been started for about 15 seconds to a minute most of those 4 days, Another is the exhaust smells like 10 times stronger than exhausts normally smell, the car does runs strong and everything, no leaks or weird sounds. Also, it will occasionally stall at redlights, its done it about 2-3 times. This is usually 70-80 degree weather in the afternoon, 60's in the early early mornings.

its a 2.8 V6 3 Speed Auto.

[Money pit Beretta]

Have you cleaned the IAC port? Kind of sounds like the IAC is sticking.

[GTU89]

Ok, whats a IAC port? Sorry, I'm only 17 so I don't know a whole lot about these things..

The smell is probably because the previous owner punched the cat out. Also, my digital dash is starting to act strange, it seemed to be ok before I my sub and amp were hooked up, sometimes it is fine, other times it will show random numbers/half letter things where the speed should be, like It wil say im going 198MPH while i'm idling. or it will just plain show weird number/letters and not update the speed at all. I've only had the car about a week so far. I'm happy with it though, body's really nice, no rust or paint peeling.

[GTU89]

Oh, IAC is Idle Air Control, sorry. haha.

Any ideas about the other probs?

[ronaconda]

Sounds like your cluster is going bye bye

[SuzukiGhostRider]

Check the IAC first at MPB suggested. It's only two torx head bolts, and it's located on the TB (Throttle Body, it attaches right at the UIM (Upper Intake Manifold) at the engine end of your air intake hose). The IAC looks like a D battery with an electrical connector attached to it, and is connected directly into the TB. Just unbolt the IAC, pull it out, clean the spring and shaft with a can of Carb Cleaner, make sure the rubber o-ring on it is in good condition and re-install it and see what happens.

You could try an idle relearn first though. Disconnect the car's negative battery cable for about 5 minutes. This will reset all DTC's (Diagnostic Trouble Codes) if any are present and force the car's computer to relearn how to idle properly when you reconnect the negative cable. After you reconnect the negative cable, start the car and DO NOT touch the gas pedal NO MATTER WHAT. Let it idle for about 15 minutes to get warm. Shut it off, wait about 5 minutes and repeat. Do a total of three times. The idle will sound really bad at first, but it will get better as the car cycles through the the three idling periods.

If neither one of these solutions work or both of these solutions fail, I would lean to a bad O2 sensor. That is located on the side of the exhaust manifold. Looks like a spark plug with a single wire connection plugged into it.

Welcome to Bnet. Glad to see the new generation still thinks this (the Beretta) is a cool ride!

[ronaconda]

To do a proper idle re-learn, so i have been told, the engine needs to be under a load. This is how i was told to do it and how i have done it on my 89...set the parking brake. Start the car. Put the car in drive, turn on lights and the HVAC fan on hi. If your A/C works, DO NOT turn it on. (If your parking brake works, it will hold the car from moving in drive.) Let it idle like this through an ENTIRE fan cycle (until it turns off). Put the car in park and turn everything off. Let it stabilize for a few seconds and you're done.

[SuzukiGhostRider]

Never heard of that Ron.

[berettaboi]

i have never heard of doing it in gear, but i like to load up the charging system with the lights and hvac fan while relearning. i'm not sure if it actually factors in the amperage draw in conjunction with the idle speed, but yeah.

[GTU89]

Ok, I'll try that stuff. Could it be a injector maybe?

I love this car tho, it's even got the original leather/vinyl book thing with all the original warranty and owners manual things, there's 3 books i think and the original salesman card from when it was bought new. Rust free too, which is a bit surprising for a 20-something year old car in PA.

[SuzukiGhostRider]

When doing an idle relearn, the ONLY thing you're trying to get the car to learn is the BASELINE idle. IE: No A/C , no blower fan, no lights,etc. Once you have taught the car it's baseline idle, everything else will fall into place as the system already knows how/when to compensate for things like A/C (TPS Sensor does that) , lights, HVAC, etc.

[GTU89]

When doing an idle relearn, the ONLY thing you're trying to get the car to learn is the BASELINE idle. IE: No A/C , no blower fan, no lights,etc. Once you have taught the car it's baseline idle, everything else will fall into place as the system already knows how/when to compensate for things like A/C (TPS Sensor does that) , lights, HVAC, etc.

Well, this is a late reply, but I fixed the idle and the digital dash by unhooking the battery for awhile, there was practically no battery ground at all, so I fixed that and it seems to be all good. (Digital dash's problem was the lack of a battery ground and the idle i guess was fixed by the computer relearning the idle) its been about a week or so since I fixed it and its been fine since then

I guess if the digital dash goes out I can always go to the local junkard (they have like 15 or more berettas there, atleast two nice GTU's, a CL and a Indy)

[SuzukiGhostRider]

Sweet. Glad to hear it man.

On a side note:

Any blue interiors? I need some parts for the Z.