rrrghhh Need Help... 87 sub, running rough...

[rgilmartin]

running rough, very hesitant at the low end of the gears, but will accelerate and run better at higher rpm's..runs great for first minute after or so after starting..

a little cough at idle, recently started stalling when idling in D and it's hot out...

Did the 'tune-up thing, probably needed most of this anyway'... plugs, wires, cap and rotor. Changed fuel filter and O2 sensor.

sprayed carb cleaner around intake and tbi to check for vac leak, no difference.

cut off cat, was 'sure' it was clogged, it wasn't....

now what??

Thanks!!

-Ryan

 

[rgilmartin]

Oh yeah,

also checked the TPS voltage, it was around .5 volts and went up when throttle was applied.

Have gotten a code 45, "rich condition"

Plunger on EGR moves, tried disconnecting vac line to it, no change.

 

[Snowy Rivers]

I would be looking at the distributor itself. These get tired after a while.

The module in the distributor as well as the pickup coil down under the lower plate can get tired.

Pull the cap off and crank the thing to get the rotor pointing to the front and then yank out the distributor.

I will bet that the thing may turn hard and or have a lot of crap falling out of the pickup coil area.

Fresh rebuilt unit with anew module may fix all of the issues.

The pickup coil not only controls the ignition, it controls the TBI too.

If the Pickup coil gets Hinky the TBI can and will do really strange things.

Hope this helps

Snowy

 

[rgilmartin]

Thanks for the response,

pulled the cap, dont know what these should really look like, ie whats bad and whats not...there was a lot of yellowish junk in the bottom of the dist, the ?pick up coil? was corroded inside, there was a little wire connector that was kind of melted at the bottom...the whole thing looked pretty ugly, but dont know if it was really bad....

Found a MSD Ignition, Coil, and 6A box on CL for $150,

I put the dist and coil on, got no spark, swapped the coil for the orig. one and it ran, just like before....OH YEAH, I HAVE NO TIMING MARKS, I think they bolt on to the block? Ill have to search a junk yard, I set it to about where I thought it should be, and where it seemed to run the best...

I swapped the fuel injectors for some I had picked up at a junkyard a while back, the spray pattern looks a little 'mistier', but not much improvement in performance...

Also plugged all vacuum lines at the TB, except for MAP sensor, to eliminate any of this causing a problem.

still the same performance...

Noticed that the intake was leaking at the front of the block, on both sides.

Planning on pulling intake, cleaning, new gaskets...

I'm going to have another vehicle to drive from 9/9 to 9/19 and am planning on this and some other changes...