i got a new computor, the old one was burnt out. i need to check the resistance of all of the suff like the selenoids before i put a new one in. how do you check this? what tools do you need and how much will it cost. i have the new computor but i don't want to take the chance of it being burnt out again. thx

 

You'll want to get a factory shop manual- not a CHilton's or Haynes. They give you diagnostic trees to check all sorts of resistances/voltages over the various pin locations.

My brother went through all this with his 87 recently trying to figure out why he kept blowing ignition modules. Turned out to be bad grounds (several) in the ECM itself and a flaky wire in the wiring harness. Took HOURS of checking and testing. Scillions of tests. New ECM and a fixed wire later and it runs like a champ now.

 

i got the tester. i tested the MCS and got a reading of about .5 ohms. i think i'm doing it right, but i check another car that everything works on and it was the same? the instructions on the computer say that everything is soposed to be over 20omhs. i don't get it. am i doing something wrong, or is that the way its soposed to be?

can you get me a list of everything to check so that the ecm dosn't go out again?

 

.5 ohms is way too low. Seems like it's in the neighborhood of a few tens of ohms or so between its 2 terminals, but it's been a while since I last checked one.

Should be in excess of 20 Mohms between either terminal and ground.

If your MCS actually has less than 1 ohm of resistance, it will narfle the drivers in the ECM for sure, and you'll be buying another one of those. Don't power itup if it's really like that.

 

i got it. i didn't have it set exactly at 0 and i didn't multiply it by 10. it came out to be 25ohms. i put the new ecm in and it dosn't run as rich as it did before but i think i have a bad 02 sensor that is causing it to run a little rich still.