chamm

I have a 2002 C32 with 112000 miles. The other night I had lost all power , the car would shake violently, and the check engine light started to blink. I was 5 minutes from home so I limped home and shut off the car.. Ipulled the codes are this is what I got:

p0300 multiple/random cyclinder misfires
p0301 Cyclinder 1 misfire
p0302 Cyc. 2 misfire
p0303 Cyc. 3 misfire
p0304 Cyc. 4 misfire
p0305 Cyc. 5 misfire
p0306 Cyc. 6 misfire
p0730 Incorrect gear ratio
p2311 CAN communication with the engine system is faulty
p2312 CAN communication with the engine system is faulty or engine temperature is implausible
p2500 The transmission has an impermissible transmission ratio.
p2600 The voltage supply of circuit 87 has undervoltage.
p2602 The voltage supply of the valves is faulty.

I have searched on the forum, and found some answers for the misfires, but I have not seen a problem with this many misfires, being 5 of 6 cyclinders, it hard for me to believe that it is the coil packs, plugs, wires or the cats. I am going to still pull all the plugs and take a look, as well as rotate the coil packs around to see what happens.

As far as the last 5 codes, these were pulled from the Transmission control unit, the transmission has been replaced once, and is still under warranty, so it is going into the shop on Wed.

I am really stumped on the misfires, any help is greatly appriciated.
Thanks

loudandheard

This might sound dumb, but it could be the battery. Have you checked the battery or the alternator?

Gramma_Benz

Have you started the car again since?

I'm thinking that it's an underlying problem that cause it to go into limp mode and caused these misfires. I had something like this happen once before when I needed my TPS(Throttle body actuator) rebuilt.

Car shut down, shook violently, went into limp mode and threw all kind of misfire codes. But when I started it up again, it ran fine again. Then again, it's your car, so I don't want you to do something you're not sure of.....

Get it to a shop quickly regardless.

Good luck Chamm!

TemjinX2

the transmission codes could be from low transmission fluid to low voltage from the battery.

Have you changed your spark plug wires? I got various misfires like that when i had the mag wires, when i went back to oem, the mis fires were gone.

Also how fast were you going? If your on stock plugs and your hitting 110mph on stock

plugs you can get misfires if your running upgraded pulleys. You need them gaped to .034 i believe. I think stock is .038.

Lenin

Clear the codes. Start the car and read the codes again. When I had my cam problem, all of the P301-P306 showed up but the problem was only with cylinder 6.
Also, unlikely but still possible is bad gas. Did you get gas that day?

chamm

Update: I pulled all the plugs and checked all the plug wires. Everything looked fine. They are stock wires and I changed my plugs about 12000 miles ago. I gapped them at the time I put them in but didn't recheck the gap. I was told that my throtle actuartor was giving eratic readings. Could this cause misfires? I have driven for about 30 miles since resetting the codes and it seems to be running perfect. Before the problem would come and go, sometimes the cel would be on other times it is not on. It is very eratic and sometimes it will come on and off multiple times while driving.

The car is going in for transmission work tomorrow so I'll just wait and see what they say.

Gramma_Benz

If you left it at the gap the plugs came with, that could very likely be the problem. With force Induction engines, it's possible that the plugs can get "blown out" under high boost. Much like blowing out a match.
Check your gap and if that doesn't work, get your TPS checked out.