C4 Corvette - Code 42

In my efforts to find a solution to my code 42 problem, I found a lot of useful information that I think might be helpful to others. Going into this, I didn't know much about the EST system or cars in general (my background is in computer science). It was a learning experience for me - so don't flame me too much for not knowing what I'm doing. Hopefully this will help someone else who's having trouble tracing down their code 42.

[@jimgagne3801]

This is the best video because it is the most informative and gets to the point quickly , without nonsense. that does not waste my fucking time like so many other KZbin videos that, the person making the video really wants to be a movie star and has shaky camera angles that move around too quickly. well done. this is the same thing my toilet is doing.

[@joef2593]

Very comprehensive and educational, thanks!!

[@TheBlkac1]

Yours was doing the same thing as mine...I'm gonna look for a computer. But after i change the plugs first. Now all you need is that speed cluster. I have that problem, mine works sometime....kinda like my check engine light. thanks for the video! I sub to your chanel

[@oswaldpino1038]

GREAT VIDEO N INFORMATIVE

[@garymachen7354]

This is a great video. I know someone with a 96 Suburban which when tested revealed a trouble code 42. The engine runs rough just above idle and when revving the engine, it almost dies after the rpms drop back down. I replaced the ignition control module but the problem still persists

[@SamForbis]

Thanks for the comment. As far as I know, they stopped using these older two-digit codes after OBD-2 came along in 1996. The '96 Suburban would be using OBD-2, so it's unlikely that the cause for their code 42 would be the same as this code 42.

[@ronreagan1457]

Nice video.

[@wtf0101]

Bang on the block and see if knock sensor is working

[@lukecarleton4874]

Going to look at an 87 corvette this weekend, obd1 scanner to check codes?

[@Sk1ds87]

I had a very similar problem when I bought my '86 Corvette. The car ran fine, but it always showed the SES light. In some cases, usually after a period of driving, turning off and on the car made the SES light stay off and the car ran even better. Eventually, when the SES light was on, the engine always stalled after a couple of minutes of driving. I replaced the ECM and I've never seen that code 42 again.

[@donellis185]

Will a 1986 corvette computer work in a 1996 Camaro?

[@Sk1ds87]

@@donellis185 No, it's a completely different unit. Or do you mean a 1986 Camaro?

[@slickthasloth5441]

My check engine light turns on and off and idle rpm is 7 is that normal? just got the car 1984 corvette also when I turn key it won't start at the first try

[@SamForbis]

Unfortunately the 1984 model is a bit different than other C4s. I'm pretty sure they use an entirely different ECM and may have different codes. For what it's worth, my L98 1987 idles around 550. Also, apologies for the 8 month late reply - I don't check the comments too often.

[@dinomartin7280]

Having the same problem with my 89 C4 wondering if you could let me know where you got the computer from

[@SamForbis]

I got it on eBay. It was used, out of a 1989 firebird. As long as the part number matches you're good. Just swap the memcal/PROM from your old ECM into the "new" one.

[@donellis185]

Every day is a school.

[@toddsmith3002]

Swapped PROM Chip ?????? How

[@SamForbis]

The ECM on these C4s were used in a number of GM vehicles at the time. They all have a memcal chip which contains a PROM which contains instructions and values specific to a model (Corvette, Firebird, Camaro, etc.) It is socketed inside the ECM housing and must be transferred to any "new" ECM you get.

[@jasonwysong7625]

Nasty lip smacking. Geezus. Microphone in your mouth or what?

[@SamForbis]

Sorry. Guess I had it too close.

[@whitenas]

CRACKED ME UP

[@donellis185]

Every day is a school.