'87 TBI 350 Troubles

[Jake292]

yeah I got a voltmeter and i can test circuts fairly well.

 

[Jake292]

yeah I got a voltmeter and i can test circuts fairly well.

 

[Jake292]

Ok...do you have a digital volt meter, and experience in testin circuts....what i want you do do is pretty simple.

I have a volt meter and can test cirsuits. what would you like me to check?

 

[Jims86]

behind the glovebox, pull the ECM out. on the plugs, look carefully at the beginning of each row. you will notice that each row is identified as A and B on the small connector, and C and D on the large one, and then each wire has a number. on the large connector, locate row D, wire 6. set your meter on continuity, and insert one of the test in cavity 6 now unplug the connector from the ECM. now pull the 4 wire plug off of the distributor. now touch the other probe to ground...hopefully, you dont hear anything. I want to see if maybe the bypass wire is chaffing somewhere.
BTW-when you say you have MSD, what exactly do you have? a whole system, or just the coil?

 

[Jake292]

BTW-when you say you have MSD, what exactly do you have? a whole system, or just the coil?

its an 6a ignition control.

 

[Jake292]

i will check the circuts tomarrow as it has been raining here for the past few days and when i was going to work on it the rain picked up alot so ill do it tomarrow.

 

[Jims86]

Ok. I would get rid of that MSD crap untill this problem is figured out....it may be the problem.

 

[MrMarty51]

Maby could be the EGR valve is stuck open,maby.thats all.

 

[Jake292]

Maby could be the EGR valve is stuck open,maby.thats all.

I checked the valve all ready. It has 20 in of vaccum off idle going to it and I can push the valve open and it goes back to close. Also if it was the egr valve, the problem would go away when you open the throttle.

 

[Jake292]

behind the glovebox, pull the ECM out. on the plugs, look carefully at the beginning of each row. you will notice that each row is identified as A and B on the small connector, and C and D on the large one, and then each wire has a number. on the large connector, locate row D, wire 6. set your meter on continuity, and insert one of the test in cavity 6 now unplug the connector from the ECM. now pull the 4 wire plug off of the distributor. now touch the other probe to ground...hopefully, you dont hear anything. I want to see if maybe the bypass wire is chaffing somewhere.
BTW-when you say you have MSD, what exactly do you have? a whole system, or just the coil?

no sound

 

[Jims86]

no sound

Ok, so its not grounding out. Good.
This is baffling. Take the MSD out of the mix, and see how it does without it.

 

[Jake292]

Ok will do.

I've got a obd1 cable ordered so in a week or so I'll hook it up to the computer with tunepro and see what it's doing

 

[Jims86]

Ok will do.

I've got a obd1 cable ordered so in a week or so I'll hook it up to the computer with tunepro and see what it's doing

That would be awsome...use Tunerpro RT, and you can send me the file. Keep in mind, there is the possibility we are chasing a mechanical problem. If you have not done so already, try to get an AC Delco 02 sensor and throw it in there.

 

[Jake292]

I know that there is a possibility that it is a mechanical problem. however, i feel that it is most likely something with the computer because the problem stops when the timing control is bypassed

 

[89Suburban]

Did you find a good deal on that ALDL cable?