Glen Gonyea

Have a 1993 CH 613 E7 400... Boss wants to switch to a mechanical fuel system..anyone willing to share any expirence of decent success with this. The problem with the truck now is it runs but has no power..when I hook the MODIS to it its like the software is blank and has computer issues... I think it needs a new VMAC module.

Or where can I find it one?.tryed the mack site does not seem to work, must be missing something. Or what's a good place on the net to buy this type of info? There is so many of them, anyone had luck with a pirtclier site....

Doing head gasket replacement on 93 e7. Anyone on here have a pdf engine service manual that you could throw to me?

Where did you purchase the new ECU's? Dealer? Used one?

Yup I never get the easy one...I'm going to call around and see if I can find a test module...its good info, thanks...any input on this will help out..This could be a costly repair I have to get this right....Is there a website that has wiring and troubleshooting diagrams of sorts for macks..at a good price of course..

I have a 1993 CH613 E7-400 no start..Used to run fine but is shut down and has not started on its own.It looked at first the issue was at the harness plug from the back of the injection pump...We removed and soldered the wiring but still have a issue..OK but I can get it to start by adding a quick ground to pins 1 or 2 at the ecm(output to the fuel actuator)..beceause when I remove the shutdown relay put the powerprobe at pin 87 i have a ground feed from ecm through fuel actuator but when i turn the key on it drops out..grounds have been cleaned and checked on the truck.. Also when its running the RPM gage does not work either, same there if during cranking I add a quick ground to pin M4 on the gage cluster it starts and runs...1. it almost like a ground in the ECM is bad 2. but if the ECM was bad would it run at all? 3. when it does run there is no tach (looks like the ECM processes the tach signal) Questions 1. does any one have a in depth wiring diagram of the bosch ECM for this? I have the basic VMAC diagram 2. If I replace the ECM would a ECM from any 1994 E7-400 work? Does the dealer need to program a used ECM 3. or is there a oil sensor signal needed to give this ecm a ground to start up? 4. Am I missing some stupid here