OK, I have been doing an engine swap, putting a 350 TPI engine into my 1964 GMC truck.

I bought a 85 vette MAF motor w/700R4, then bought a harness kit to upgrade to the 90-92 speed density with MAP sensor. This also came with a 7730 ECM, and a custom chip the had NO VATS, or emissions.....


Now, it's been about a year, and with everything wired up, I get no signal from the ECM.....No SES light....Fuel pump runs but won't turn off....everything else works....

soooo, what are the chances that the ECM is bad, and the custom chip is good?

any way to check this other than getting another ECM, and trying it?



Any help would be great!! I'm right at the point of jerking the TPI off and throwing a carb and intake on it, but that means I have wasted a lot of time and money, plus I like the way the TPI looks under the hood...





So throw your idea's my way.......any questions you need answered about what I did, anything.....

Thanks


Chad

 

go back over the wiring, make sure all the powers & grounds are right.
a bad ground some where can drive you nuts.
if everything checks out good then its probably time to try another ECM.
fortunately the 7730 ECM is pretty common & came in a fair number of GM cars.
https://www.thirdgen.org/ecminterchange

if you can find one from a camaro or firebird with the right MEMCAL in it, it could help you in deciding if you have problems with the chip.
ANJA & ANJF are both good Bcc numbers for the 90~92 350 7730 TPI systems, AUJP is the latest & the preferred Bcc.

 

Thanks, I have checked everything, and it looks like it is the ECM.

On the page above, they have 3 different ECM's listed ..7730, 6344, and 8262.

Can any of these interchange, as long as I have the correct Prom chip?

I was able to get a 6344 but wanted to make sure I could use it before I tried it....

Thanks

Chad

 

no problem
yes, they are interchangeable, the 2 16xxxxxx are updated ECMs. there may or may not be improvements in them.
the PROM is what makes them work properly for each different vehicle.

 

Well, I found out that I did not have an oil pressure switch.......I just had the 1 wire sensor....

so a quick trip to autozonwe got the right sensor....

also found out, I had the fuel pump run off the underdash harness.....thats why it ran all the time.....

I hooked it up to the wire off the ECM, installed the Oil-pressure switch...turned the key and .......NOTHING....

well, it cranks over and all, the gauges and all the light work execpt the SES


still troubleshooting..........will spend most of the afternoon on it....

still not getting a light for my SES.......

this sucks......



thanks for all the help though......

 

well, after telling you I had checked the wires...


today me and my son checked the pin outs for voltage, and then dicovered I had some wires hooked up wrong.....

after about 2 hours, it cranks!!!!

very loud without any exhaust of course.....


thanks for all the help



Chad