Chevy Cavalier computer issues PLEASE READ THIS!!!

[big papa]

I have purchased two Cavariers lately that unknowingly have had the same problem and as we all know, it is costly to fix.

The computer has been poorly engineered and placed outside the protective shield of the engine compartment or the interior. This leads to unknown or at least unwanted and expensive corrosion. They can also be hit and damaged in fenderbenders. The plugs don't keep out water very well and I am in need of another Alternative fuel computer.

This computer is warranted by the manufacturer for 80,000 miles or 8 years. I think that many Cavaliers that have problems are still under warranty , but the owners may not realize it.

My question is how many of us out here in CNG land have had this issue, and can we get the manufacturer to warrantee their poor design and placement. I really need to get as MUCH FEEDBACK as possible th make a case to the "powers that be" and see if we can get a little help.

Please write here if you have experienced ANYTHING of this sort and any Ideas you may have. Thanks.

[Curtis]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

Big Papa, you might consider deleting this post, then repost it with a poll. A poll can be added in the section under the text window. Set up the poll to get the specific info you are looking for, break it down to such details as year model, ie

Had this problem on my Cavalier:
1999
2000
2001
2002
etc, and they can check the appropriate box. Allow more than one reply in case they own more than one... like you.

[freedml]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

No problem with our computer. It's always been in California where there's very little rain.

[siai47]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

I've had four Cavaliers (still have two) and have not had a problem with the Alternative fuel ECU. It is not to say that I won't but so far OK. If you think the AF ECU is in a bad place, you ought to look for the gasoline ECU that was until 2002 located just outside of the right front wheelwell down by the radiator. That seems to be a really bad place. If you think corrosion is going to be a problem, you should remove the ECU and spray some "Corrosion Block" or "Corrosion X" into the connector and reassemble. A lot of marine stores carry one or the other of these two brands. I have seen a couple of posts about failure of the ECU, but the most common expensive failure seems to be the gas mass sensor.

[sradabaugh]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

I own a 2000 cavalier and I am ordering a new computer for it because of the poor outside placement of such an important electronic component
thanks,
SRadabaugh

[chinos]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

i had work on a couple 2002 cavaliers saemes that the problem i see is mass air flow sensor for some reason looses ground at the internal chasis in the module ,i been able to take apart , cleaned and worked beutifull

[ericguy320]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

There was a recall for 95-99 cavalier's in the rust belt to add a cover over the PCM. "Product Emission 99090"

[macutak]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

Where did you order you new computer and for how much? I need to get a new alternative fuel ECU for my 01 cavalier and cant find one for under 1200$.

[Mino1984]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

I am having the exact same problem. Where is the ground Chassis on the 2003 Model? I can't find any photos or instructions of how to do this. I replaced the sensor, the connector, and the mechanic wants 80.00 just to look at it.

[siai47]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

The question you are asking doesn't relate at all to this thread. The 2003 Cavalier does not have a AF ECU therefore corrosion issues don't apply to your vehicle. As far as the ground is concerned on the '03, follow the battery negative cable. It first grounds at the battery tray and then continues on to the engine block. It's kind of hard to get to as easy access is blocked by the low pressure regulator. However, this ground point has been a problem in the past. The cables should be removed first from the tray and then from the stud on the engine block and cleaned with something like a Scotchbrite pad. The cables should be reinstalled and the entire area should be coated with a corrosion protector---WD40 will work for awhile---for something more permanent try LPS #3 or Boeshield T-9. If your transmission acts a little strange after disconnecting the battery don't worry---it will reprogram itself after a few miles.

[pearceri]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

Yes, I think I have this problem now. I have seen this on several cng cavaliers. It is a very poor design. I talked to my dealer yesterday, and they told me GM put out a bullitin on cng cavaliers up throught 1999 to put a boot over the computer. I don't know why it stopped at 1999. The one I working on now is a 2002. The 2003 and 2004 are a completely different design, and work well. I don't know what we are supposed to do with the older ones. GM used to be receptive to addressing things outside of warranty, but don't seem much interested anymore. I agree something should be done.

Bob

[sradabaugh]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

I ordered from the LKQ company. It was a used one. I couldn't find any other supplier.

[siai47]

Re: Chevy Cavalier computer issues PLEASE READ THIS!!!

Any one of the AF-ECU's from GM vehicles from '99 through '02 can be made to work. '98's will work but they are not OBD II compliant. They must be re-flashed with the proper "calibration" to be compatible with your car. '99 through '01 Cavalier computers should interchange without re-calibration, however your '02 is a one year deal with the later model ECM---so only a '02 will work without re-calibration. Look for some of my old posts on this site about taking the housings apart and sealing them to keep corrosion out. Even if you found a brand new unit, you should reseal it before you install it. If you need re-calibration, install the AF-ECU and keep the CNG fuse out until you get the car to a dealer or someone who has a Tech2 flash and access to GM techline to get the proper calibration loaded into the AF-ECU.