DME was very very hot, like it almost burned me.

It died while driving, it stopped firing. Before this it ran super rich, like 9 to 1, and idled at 500 rpms, for about 5 minutes, I was trying to make it home.

Now there is no spark, but the Link ECU reads rpm and map. Could an injector ballast resistor wire coming loose cause an excess of current to remain in the DME and overheat everything? I think I found one connection falling apart.

Fuses are good, the DME relay smells ok.

I am powering my boost guage and Tech edge wideband off of separate wires from the battery, not the dme. I will check the grounds tomorrow, I know that is a coommon cause of DME overheating.

If the DME did overheat, what happend? I looked at the circuit boards and they are not clearly burned anywhere.

ANy input is appretiated,
Thanks

 

Just ouf of curiosity, what impedence are your injectors? How many ohms?

 

Im not sure, but they are siemens 55lbs

 

Well, if you are running a low-impedence injector (typically 2.5 ohms) and a ballast resistor came loose, then there is no question that your DME will eventually overheat. Did you install the injectors or the PO?

 

I did install them. Thank you! I will try another dme today and post back. I hope its not the DME chip that fried, thats the only thing I dont have another of.

 

Although this running rich thing is weird, I am positive it was, as I was using the tech edge. Wouldnt a ballast resistor coming loose make it run lean?

 

When you say ballast resistor came loose. Do you mean, that it was disconnected from the wire? If so, the two injectors on the other end would stop fireing.

 

Sorry to hijack the thread, but why are you using ballast resistors on Siemens injectors?

 

Because danno says to basically, I didnt do any calculations out or anything. I mean the wire came loose. It is looking more like a short somewhere in the DME/fuel/ignition wiring, I just need to find out where before using the replacement dme. Maybe my fuel pressure regulator is stuck, i know this causes the dme to overheat sometimes.

 

Update, it was fixed, with a combination of tapping on the FPR, adding grounds to the DME, and redoing all he ballast resistor connections. Not sure which did it, but the DME is running cool now. Thanks to all who replied.

 

 

Check your grounds also. If the engine-block grounds are corroded, the current that normally goes through them ends up going through the DME's ground.