92 Bonneville - bouncy idle and won't go into closed loop
 

Hey, first off, I appreciate anyone willing to help me here. This is my first post on this board, as I don't own the bonnie in question, my gf does. If you have a Jeep or a Diesel, I can help you. But I'm at a loss here. I've searched the forums and google but have found nothing to help yet. Sooo....here we go..

1. Idle bounces between 600 to 1000 at idle. I have replaced the fuel pressure regulator, and the vacuum line (two different size nipples?!), but i don't guarantee there is no vacuum leak.

2. Tranny shifts into 2nd early, it just jumps right in. Hits 3rd too soon as well. Is now starting to hunt for gears on the highway. It locks and unlocks the t.c. in 4th every 20 to 30 seconds.

3. Won't go into open loop, it complains about a faulty o2 circuit. The o2 sensor is brand new. The exhaust smells terrible, rotten egg style, but the cat is new. It is running rich.

What I've replaced:
o2 sensor
spark plugs
throttle position sensor
fuel pressure regulator
2 of the rubber adapters for the vacuum line. The two nipples off the front of the vacuum distribution block
catalytic converter

So, if anyone can offer some advice. What to check, where to look, I'd grealy appreciate it.

Darren.. click Techinfo at the top of the page and use the procedure to pull your codes.

You mention an O2 code..I'm wondering if theres any others as well. Expect 58? the standard known bug.

During all of this work have you unplugged the battery for 1/2 hour and then reconnected?

Primarily I'm gathering info for the guys with more experience on your year.

I had a similar problem.............I changed the O2 & MAP sensors and the idle stablized, but I did not have any problems with my tranny, that might be a seperate problem.

Good luck,
Dutch

I'm thinking it might be the MAF sensor? I know it's a variable for load which tells the trans when to shift.

Mostly guesswork here without a scan, but unless your car is Supercharged, you can forget the MAP sensor. Only supercharged models got one.

My first guess with a wandering idle would be a dirty TB. I suggest pulling it, cleaning it thoroughly with all sensors removed, and reinstalling with a fresh gasket. They typically like their first cleaning (particularly the IAC passage) at 60k miles or so.

The car isn't supercharged, it comes equipped with 182k miles.

The TB gasket was fine when I took it off. The IAC, I think, got a healthy dose of brake cleaner already. Is there a way to check if the mass airflow sensor is bad?

I ran a scan w/ the scan tool, and got the bad o2 circuit message. Last time I ran tried to run the scan the computer wouldn't connect to the scan tool.

Does the vacuum distributor go bad on these cars?

I really appreciate any input & help.

Brake cleaner??? It's a throttle body, TB cleaner contains cleaners and lubricants for air only areas. I hope the brake clean didn't wipe out any of the sensors.

There is no vacuum distributor to say. The vacuum rubber fittings and rubber connecting pieces do dry rot and go bad. I've replaced most on my 97 out of necessity.

Brake cleaner is absolutely the worst solvent you can use on anything other than brakes. You may have damaged your MAF, O2, IAC, or TPS with it. Even if they were off, the residue may have still been there when the sensors were reinstalled. Use a cleaner labeled as 'intake' or 'sensor safe'. And don't get anything on your MAF sensor other than rubbing alcohol and a q-tip.

well, nothing has gotten any worse since the cleaning so I'm giong to assume little to no damage was done, for now. I've never seen a bottle of 'sensor safe' cleaner. Guess I'll need to look harder.

IF you want come into gr sunday. I will be at the meet would be happy to look at with u> I am not is skilled is Willren or billboost. I do have some left hose when I replace my vacum line stuff is cheap thought. I have about 1 foot 1.5 left. Of course they will be others to that I am sure would help look to. I will take it with me and replace what lines look bad. I always have handful of tools in my car at all times
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