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major loss of power


92bonny
03-11-2004, 11:57 PM
Hello everybody,
I am having an issue with a major loss of power in my 92 bonneville se. The car can barely hit 30 going uphill and barely does 60 on the freeway (takes about 25 sec or more). Also the car hesitates up to 3500rpm no matter what gear it's in (was 4500rpm but it got worse in about a day) then stops and stays there and starts decellerating. Also if it's in nuteral the car won't rev past 4500rpm and then starts making a hissing sound in short spurts coming from the engine compartment and pings rather abruptly. Also the car sounds like it might be choking a little and the exhaust smells a little funny. I took it to the dealer about a month ago (before the problems were this bad, the car used to hestiate but all of a sudden it started doing this) and they said the cam sensor was out and the timing chain needed replacing, something about a magnet falling off that tells the computer when to fire each cylinder. I figured maybe now the catalytic converter went out but am not sure. If someone could help me out I would really appreciate it.

jkinney
03-12-2004, 08:33 PM
You could have a few things going on here, but the first thing I would do is check the plug/wires and O2 sensor. These engines are great, but can go through them pretty regularly if you dont have good ones. The magnet can come off the cam sprocket like they said, but not sure if it would run at all if the cam sensor wasnt sending a signal, but it does set up the timing position with the crank sensor, so if it did run, it wouldnt be pretty. That would explain the "smell" you talked about, unburnt gases.... Replacing the sensor magnet isnt real bad, but if your not equipped, or new at it,... it can be tedious. BTW you can check the signal coming from the cam sensor to see if it it functioning properly. How many miles, and when was the last tune-up?

int_53185
03-13-2004, 10:43 AM
sounds like a cylinder or two is dead...first thing to check on these engines is the spark plug wires...had a bad one on mine..barely ran....

92bonny
03-14-2004, 07:07 PM
Thanks for the replies, I was just wondering how I would know if my wires are bad. Also where might I be able to get info on replacing the sensor magnet, the dealer told me the whole timing chain needed replacing. By the way the car has 105,000 miles and had a tune up 1 year ago. I also had the catylitic converter replaced with a high flow one which fixed the high rpm stalling but the car still stutters alot. Thanks alot in advance for anymore replies.

int_53185
03-14-2004, 10:44 PM
one way to tell if u have a bad spark plug wire is to take a spray bottle filled with water and carefully spray the wires while the car is running...any change in idle will tell you which wire is bad...sometimes wires are bad right out of the box...another way is to measure the resistance with an ohmeter....i just re-replaced the wires in my wifes van...one had corrosion under the terminal...the age of your wires has nothing to do with wether they are good or not....just a little bit of experience ive had with my tuneups...also if dielectric grease wasnt used under the terminal ends of the wires...water may seep underneath and corrode the terminals....

BonneMeMn
03-21-2004, 05:26 PM
The car has a rev limiter of 4000 below 19 MPH. This is to protect the valvetrain, Free-reving is a very quick way to send heads into oblivion. Don't do it!

Check all of the wires/plugs, look at the throttle body. The Cam sensor may be part of it, but that's not an easy fix. Tranny may be at fault here.

A clogged cat will cause the car to suffer at higher RPMS, around 30 and 60 MPH as well.

92bonny
03-24-2004, 04:52 PM
Turns out it was the cat and my plugs could use a change, thanks for the help everyone.

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