Urgent Motor Help Needed After Tuneup

[Nick88]

Hey guys Ive been chasing a misfire on my 1988 TBI 350 Blazer on start. I just did the intake manifold gasket that was much needed and now today I put in new AC Delco plug wires again. The plug wires seemed to help the mis so I decided to clean out the motor a bit since I noticed a lot of gunk on the valves when I did the intake. I had my brother hold the truck at 2000 while I did the classic pee stream of water into the intake. I noticed the motor bogged a lot more when I sprayed the driver side of the throttle body compared to passenger. After I was done the driver had a pretty constant stream of blue smoke which went away after revving then shutting and restarting the motor. Now the notor idles like crap, has good power driving but once it hits idle the truck vibrated a ton and the driver side tip sounds almost like its chugging. The rpms do not bounce at all and arent particularly high, the IAC position is 8 in park after driving a while. The driver tip has a harsh oily smell in exhaust, passenger has almost no smell. Any ideas what could be wrong? Please any help is greatly appreciated anyone!!!

 

[Nick88]

Anyone?

 

[fisher]

Anyone?

Change the spark plugs too?

 

[GoToGuy]

The water in the throttle body. This is something that must be accomplished with great care. Water is not compressible. Have you converted to dual exhaust? Stock is two into cat then one pipe to rear or dual split after cat.
Pull plugs what do you see. Firing order correct? Wire snapped on, no gaps.

 

[Nick88]

Good news, had to leave for a road trip after I parked the truck which is when I posted this thread, just got back and looked around the motor, turns out one of the back plug wires somehow popped off the sparkplug. I was extremely relieved I didnt blow something up.

 

[Erik the Awful]

For future reference, the factory manifold is a dual plane. The driver's side of the TBI feeds 2, 3, 5, and 8. The passenger feeds 1, 4, 6, and 7.

If dribbling water into the driver's side makes it run rough, I'd consider that 1, 4, 6, and 7 aren't contributing enough.

 

[Nick88]

For future reference, the factory manifold is a dual plane. The driver's side of the TBI feeds 2, 3, 5, and 8. The passenger feeds 1, 4, 6, and 7.

If dribbling water into the driver's side makes it run rough, I'd consider that 1, 4, 6, and 7 aren't contributing enough.

Yep! I knew the injector pods split across the motor each way, just wasnt sure what cylinders to which. I knew it was a cylinder on the driver side either way because I could hear it at the tip and a tapping sound coming from the driver side, it was cylinder 5 that was down.

 

[Nick88]

Out of curiosity, would having one spark plug wire off damage the icm or the coil??? The truck drives great but at idle it smells super rich on the driver side tip and it kinda has a light surging at idle. The integrator stays pretty much around 128 but I noticed while driving the BLM is around 140-150, any ideas what could be causing this???

 

[termite]

the BLM is around 140-150

My understanding is that a BLM value above 128 indicates lean condition and ecm is commanding additional fuel to compensate (lower than 128=rich condition).

 

[Schurkey]

Yes, an open circuit (plug wire not attached to a grounded spark plug) can damage the ignition coil. A damaged coil can damage the ignition module.

When the ignition secondary (plug wire) circuit opens, the coil voltage goes sky-high. Very hard on everything, the insulation is stressed.

If you have a misfire, the O2 sensor sends a false-lean signal to the computer, driving it into rich-command. The BL goes up until the Integrator is happy.