Our vintage (1988) Jeep has been needy for attention since about 2 weeks after we bought it. I’ve replaced spark plugs, plug wires, cap, rotor, various engine sensors and rubber lines to eliminate problems reported by codes from the check engine light.

The most frequent codes were “random misfire” on cylinders 4, 5 and 6, until now unsolved by the repairs above that did eliminate the other codes that came along with the misfire codes. The other problem was the sickening smell of gasoline everywhere we drive.

The leak finally became large enough to be visible but still so small the fuel would evaporate quickly making it hard to spot. The “fuel rail” that pumps fuel to the fuel injectors has a leak at injector #3. I started shopping around for a new fuel rail but they were discontinued by Chrysler and aftermarket replacement is nearly $200 and many reviewers mentioned leaks developing on the replacements just after the 1 year warranty expires.

By this time I’m wondering why there wasn’t a recall for this problem. I started searching the forums without much luck on the topic of leaks. But I stumbled onto a thread about people having trouble with heat induced vapor lock (unheard of with fuel injected engines). But it was in these postings about insulating fuel rails I found out about performance fuel rails made from solid bilet aluminum as well as improved designs for the fuel injectors.

I found out the aluminum fuel rails do not develop leaks, keep the fuel cooler and are 2/3 the cost of original style leakers. The improved fuel injectors are actually just more modern 4 to 12 hole versions of the 1-hole injectors used in 1998. By going to a 4-hole injector, there’s less unburned fuel for better fuel economy and smoother running engine (maybe fix by random misfire codes???).

So I ordered the fuel rail and new injectors and did the swap this weekend. On top of saving money on the parts, I saved more than $300 on labor doing it myself. Don’t let anyone tell you engines controlled by computers are too complicated to work on, if anything I found out they are way easier than the older cars. You can go the Autozone/O’Reillys to have them read your codes and the electronic parts are plug & play. And for $20 I bought a Bluetooth code reader that shows results and what needs repair on my smartphone.

So far the new injectors have my engine running so much smoother, i don’t feel the random shakes from misfires and no more fuel leaks or sickening gas fumes. The documentation says it takes about 5-10 cycles of getting the engine to full operating temperature and full cool down before the engines computer gets tuned to the new injectors. Just the immediate improvement has me very optimistic about mileage improvement.