I have a 2000 pontiac bonneville ssei (supercharged). I just hit 180 thousand kilometers on it yesterday and everything went downhill.. my speed would stick to 220km/h even though i would only be going around 40. I thought it was just a problem that shouldnt need attention so i went to sleep, when i woke up the next day same problem except its happening very frequently. Someone please tell me what is wrong or what i need to do to fix this, Here is a youtube link of my problem. Thank you guys!



Thanks again guys!

if you dont have issues with shifting when the speedo is wrong, the speed signal is good to the pcm and the pcm talks to the cluster via serial data with all the other signals, so the majority of the time its the cluster

Thank you for your reply firebird, also excuse my language in the video. I love this car to death but for a 19 year old, its becoming extremely difficult to keep repairing it. I have a ton of problems with the car and only 1 "modification" and thats just a new intake system. I put it in nearly a week or two ago since this problem occurred. My shifting has becoming extremly sluggish and i feel as tho there is no torque. Small toyota matrix'* keep up with me when i push on the gas. Even in the video, i pushed full gas, like there is no more throttle to be pushed and u saw the slow, slow, slow acceleration it had.. It sucks because it was once a fast car, then im not sure what happened. We bought the car brand new back in 2000. Well, my parents did and they just handed it to me once i got my license. Do i need to change the entire cluster or is it just a plug thats gone bad? because it goes all weird like that, but when i slow down or push on the gas, it clicks back in and goes normal again. Thank you!

seems separate. if the vss was bad the trans would be sporadic. when is the last time you changed the fuel filter and plugs/wires?

as far as the gauges im not sure. i would take the cluster out, and look at the connectors first and see if anything looks loose, then reseat it a couple times then try it. if it still does it, its something inside. you might be able to find a used one at the junk yard

I think the wires were changed at 100k and now its at 180k, i might have to do it early, but hopefully its not gonna cost me my entire savings account. im going to my mechanic tomorrow and hopefully its just something small that is loose that needs to be tightened. Thank you firebird! Ill let you know what he says, and if he does it, i'm going to see if it solves the issue.

Car is also getting really bad gas mileage so im guessing maybe the o2 sensors are going bad. See what i mean when i said everything broke down at once and im struggling to keep up with it? i might just have to store it in my garage and drive another car around until i get money to repair it, because im not really ready to let it go

what about the fuel filter?

it was changed at 150k, now its 180k.. its still doing it, I spoke to someone at GM and they said my gas cap wasn't put on correctly so it let rain water in the gas tank, But ive done 3 fill ups since then.. Shouldn't it be gone by now? there are times where I turn on my car and u can hear the car running but the rpm is 0, second I put it in D it goes to 1. Its only the RPM and the Speedo, but the oil kPa or boost gauge all works normally. He said wait a week for it to clear up and if it doesn't hes going to fix it but im not sure what the problem is, and I don't want it to blow like 400 bucks. Thank you for all your help and sorry for the late reply.

sounds like dealer nonsense to me, even if you left the cap completely off it would have to rain sideways and get above the drain. as far as the gauges do you have a scanner with live data? i get the torque program for and you can see what your pcm sees on a number of inputs, its much easier to trouble shoot obd2 cars with this capability and it was $5. the obd2 bluetooth adapter is 20-30

yeah, i took it over to my buddy who is also a mechanic and he said he couldnt figure out what was wrong with it. So i just took it to the dealer, cost me 150 dollars to fix + 114 For labor. Its working all good now. I thank you firebird!

And what was the issue?