Ok, I have a 1989 Bonneville LE (love it) and I have had it since I was 16 (first and only car) im up to 193,000 miles, and something is wrong. I just all of a sudden had horrible stuttering, and there is NO power any more, it has a hard time accelerating, and is especially bad at lower RPM at high speed (highway), it almost acts as if one of the cylinders isnt having combustion, but im not a mechanic by any means, i tried the trick with the ALCL and got only Code 12, so there arent any error codes stored in the ECM. I pulled all the plugs, and none were bad. or "wet" also, I checked the wires and they are all ok. Also, i just had a new fuel pump put in about 2 months ago, and that included a new fuel filter. Please anyone know what the heck is going on, I love my bonne, and I want it to last me a lot longer than this. Thanks!!
as a side note, boo @ GM for peeling clear coat, (at least the car under it is good!) and at Macco for wanting $1200 to repaint the car

When were the plugs and wires changed? What did you do to check the wires?

I bought a spark plug wire tester. similar to the one shown here) http://www.autobarn.net/lis26900.html And the plugs were replaced yesterday. And i should have mentioned before, all the gauges read normal, as well as NO service engine soon light. The wires werent bad, so I didn't replace them, I only replaced the plugs, and I should mention, i don't think I could afford to go throwing parts at my car, I need to pinpoint whats wrong and concentrate on that.

where are you located? there might be a member close by that could give you a hand

A member close to me (crossing fingers) I live in Billings, Montana. (ack BTW) at least here they only use sand on the roads which equals no rust on cars, YAY!!! lack of technological advance, lol

Ok, start with a compression check of the engine and hook up a scan tool to see what is actually going on. (not just the error codes, but what the sensor values are.)

There'* a couple of possiblilities to poor idle and acceleration...in no particular order:

1.) Maintenance items: Bad sensor(*), dirty MAF and Throttle body, plugged up filters etc (when was the last time you replaced the fuel filter?). Obvious fix is to isolate which ones they are and clean/replace them.

2.) Poor compression...this is a killer because it can only be cylinder bores or valves..which means it is overhaul time or new long block.

3.) Plugged up cat. This is a cumulative problem and probably wouldn't show up all at once. Easy to test..disconnect the exhaust system and take it for a short drive (Put your ear plugs in and don't drive it for very long...not good running the motor with zero backpressure in the exhaust.)

4.) Leaky VAC line somewhere on the motor. This one can come on all at once when an old vac line breaks. Cheap to fix though with new rubber hose.

5.) Magnavox coil pack...if you haven't ditched this yet, consider budgeting a replacement set of Delco coils. Worst caase, get a set of used Delco coils from another list member or Ed Morad.

Yeah, I know, that'* quite a laundry list, but only the overhaul item is expensive, the rest are pretty simple and inexpensive. It'* just going to be time consuming to check out each system one at a time and find what is causing the problem.

In addition to checking all the spark-related items, check your fuel pressure. 99% of these problems are spark or fuel. Mostly spark.

as far a fuel, in response to CLM2112, they replaces the fuel filter, wehn they replaed the fuel pump, 2 months or so ago. And any ideas where to get a not so expensive scantool? Also not being a gear head, where is the coil pack, and how do I replace it, and i havent heard any slight hissing, while loooking for bad hoses, and listening very closely for a vac leak, this doesnt mean that there isnt one, just that I cant find it if there is.

Being in Montana, you don't have any members living nearby.

Your best option for a scantool is the Actron CP9110 with GM cartridge (best prices are always from eBay), and because of your funky 94/95 hybrid PCM, a cable from here:

http://www.bonnevilleclub.com/forum/...t=actron+cable

It'* possible the Actron CP9145 will work for you with the cable it comes with, but I'd need confirmation on that. I know jr's3800 knows.

Coil pack is at the other end of the spark plug wires. Big, black, rectangular looking thing on the front/passenger side of the motor near the alternator. The entire pack comes off after removing six screws. The three individual Delco coils go right on in place of the one-piece magnavox coil assembly. If you get a spark control module with the coils you can replace the entire assembly using just the three nuts on the underside of the bracket that holds the coilpack/module on the car.

Scan tool - Actron models Wilren listed are probably the easiest...I like the one I have and it works well with the '90 Bonneville, should work with your '89. Other possible tools if you have a laptop would be a GM ALDL-USB adapter from Craig Moates with one of the free-ware software packages out there (WinALDL, TunerRT, etc.) These will read and capture the values for you to analyze later.

Vac leaks are hard to find. As the rubber and plastic lines get old, they crack and get brittle. They need to be carefully inspected to find the leaks. Start tracing them one at a time. with eyeballs and fingers. I usually take the whole vac line off, clean it with hand cleaner and water, the check it with a handheld vac pump (little MightyVac) to make sure the line is OK.

On a car as old as ours, I wouldn't be looking for a single problem...there'* usually more than one in play for the car to run really crappy. If you are not a gear head, that'* no big deal...time to become one by becoming the master of your own car!