75 wagon

Newbie with a hopefully quick question. I installed a TBI system on a '75 Jeep Wagoneer with an AMC 360, 5.9 L with a comp cam 260H camshaft. The kit I bought included a custon chip, wiring harness, fuel pump & filter and adapter plate. I supplied the sensors, and I rebuilt a TB unit with new injectors, fuel pressure diaphram, etc. I am using a non-ecm HEI distributor with a tach filter.

After many problems with the order I have got it running, but have a flashing check engine light when running. I have checked for any codes and don't get any with the paper clip method. I used WinAldl and still no codes. It appears to be flashing 12 over and over again (even with no jumpers in the aldl port). I have disconnected the battery for 20 mins in attempt to clear any errors or codes.

The company claims that the Prom is fine and they tested it on their test engine. They claim it is an installation issue. The wiring harness they included was clearly marked and everything wired according to their instructions and other diagrams I have found to double check.

Any ideas of what else it could be? Possible checksum error or something?

Dewey316

how fast is it flashing?

When there is a PROM error, it will flash VERY fast.

91 camaro racer

iTrader: (2)

doesn't 12 mean that everything is fine? thats what i thought....

Ronny

iTrader: (1)

dont you have another prom you can swap in? like a stock version? only rapid CE i have seen is a bad prom/bad connection. happens often for me anyway. others blink slowly so i can read.

75 wagon

It's not flashing fast, just a steady set of flashes, a 3-5 second pause, then a single flash pause then two (I think) quick ones. It does it as soon as it is running and will not stop until the vehicle is off.

It does it with two proms from the company I got it from. I don't have the original one any more. It was used in a different project.

75 wagon

After driving it again yesterday, I noticed that it will flash once or twice, then pause, then a series of quick flashes - about eight - then long pause and start the process over.

The instructions that described connecting the light indicated the wire on the harness that goes to the computer is ground and the other light lead is connected to a 12V positive. Is that correct? Short of tearing the harness apart and tracing all of the wires anything else I can check?

BTW the computer is a 7747 if that is needed. Thanks.

dimented24x7

iTrader: (2)

Your prom is either bad or you have a poor connection. Each time it flashes thats the ecm resetting after it locks up. A series of flashes indicates a bad checksum was found and the computer halted to reset.

dimented24x7

iTrader: (2)

Another possibility is that the read speed of the eprom may be too slow for the computer. I had this problem with some el cheapo EEPROMs that I got. The speed was too slow to be reliably read.

dimented24x7

iTrader: (2)

jsut to be sure, what pin did you hook the switched wire to?