Hi all,

Now that the weather has turned cold, I haven't been able to make much progress. The repair looming over my head is to address a coolant leak, which is either an external driver side head gasket leak, or one/both of the steel heater hoses that wrap around the block, or the EGR cooling plate on the rear. Also, I'm pretty sure my oil consumption is due to a rear half moon/valve cover leak. Lastly, I have some new fuel components (injectors, fuel rail, cold start hard line) to hopefully finally address my random misfire issue. I was going to do them all at the same time, but I really wanted to isolate the misfire issue so I could drive it until the weather is nice enough for consecutive weekends to do the head gasket/timing chain/heater hose/valve cover work.

Last weekend, we had 60 degree temperatures so I decided to tackle the fuel injectors, rail and cold start line. I've never done any fuel work before and I knew it would be a bit messy, but I pushed forward regardless.

For parts, I got an OEM fuel rail, cold start hard line, and rebuilt injectors from LCE. I ordered the second set of rebuilt injectors so I didn't have to wait around to get them rebuilt, but also so I could send out my old injectors to see their before/after specs (and have a backup set on hand). Ignore the fuel filter, I'll be doing that when I do the head gasket when the lower manifold is off for easier access:





After labeling all the vacuum lines, removing/plugging the TB coolant hoses, I broke free the cold start injector line at the plenum and had a rag handy to catch the residual fuel. Then I simply removed all the upper plenum bolts (no issues surprisingly) and pulled off the plenum. Note: I have a spare plenum and manifold currently at 22REPerformance getting refurbished and powder coated, so as disgusting as the current ones are, I didn't bother cleaning them. It looks like this plenum was never removed, because the gasket was fused to the manifold. I decided against removing the gasket and putting on a new one as it would have taken hours, and the gasket was completely intact:









I managed to only slightly damage one of the fuel injector connectors (the one closest to the firewall). I also inspected the wiring and all the boots were still intact, no alarm bells there. Removed the fuel rail and promptly tipped it in the wrong direction, getting fuel everywhere. Definitely have a bigger towel here as there's a lot more fuel in this rail than the cold start injector line. Getting the fuel hard line nut on the fuel return/dampener thing off the rail proved to be a huge pain, so I threw it in a vice and used all my might to remove it. The third injector hole near the cold start line had a bunch of gunk behind it. I'm pretty sure this may have been a culprit for my random misfires/shaky warm idle. All the seals on the old injectors that go into the engine were completely deteriorated. I wouldn't be surprised if these were the original injectors from 1985:








I coated both the o-rings and the engine side seals of the injectors with some motor oil and inserted the injectors into the fuel rail first by rocking them in (see 22REPerformance's YouTube video for a fail safe way to do this). Then I put the assembled rail back into the engine and reconnected the connectors:








After this, it was simply a matter of reconnecting harnesses, coolant hoses to the TB (biggest pain getting those spring clamps back on tight), putting the plenum on and getting the vacuum hoses on correctly. It took a few cranks to start up to build fuel pressure, and I looked for fuel leaks first as I let it run for awhile. Luckily, I used all new crush washers so I had no fuel leaks. I did a test drive and did notice a coolant leak near one of the bypass hoses (the one under the thermostat). I finally purchases some offset pliers as the spring clamp was impossible to get to with any other tool. After moving it up close to the TB, the coolant leak stopped.

Results? After about 200 miles of driving, stopping and listening to the exhaust rhythm and engine, I can safely say the random misfire at warm idle is finally gone. I no longer have those random "put-puts" every 5 to 20 seconds. It runs completely smooth at warm idle, and there is no longer any hesitation on pulling the throttle.

Lessons learned? If you're struggling with a warm idle issue/rich exhaust, and don't know the age or health of your injectors, just go ahead and replace them. It took me about 3 hours and I took my time. If I didn't replace the fuel rail, it would have taken 2 hours given my struggles with the nuts on either end. With the core charge, the injectors were $250.00 for the set for 1984 to 1987 22RE's (22RE Type-C Equalized Fuel Injector Set (1983-1987)).

I'll be sending my old injectors to Witchunter for cleaning and testing. I'll very curious to see how bad these were performing.