no better way to describe it. all started new years day. was out wheeling, after a long steep climb turning high RPM's the whole way up it began to run terribly. the fan contacted the radiator and put a hole in it, so my initial thought was wet electrical system, no biggy.
Today i repaired teh radiator, rolled a core or two on it to stop the leak, good as new. fired it up and still ran horribly. checked the oil, not milky so a head gasket is not looking like the culprit. pulled plugs to see what they looked like.
first one i pulled is not a good sign, the electrode has had physical contact of some sort and has 0 gap. pulled the other 5, all look like it is running a bit rich, but not bad at all. for all i know, the first plug may have been that way from when the PO gave it a tune up. new cap, rotor, and plugs later, it seemed to run great for 20 seconds or so, then back to its old ways of missing, coughing, nearly dying at idle, along with some valve noise as well.
gonna replace wires tomorrow, but after that i am stumped. fuel pressure looks good as well, not sure what it is supposed to be, but i figure 50lbs at idle should get the job done.
check the vacuum line to the MAP sensor. that one little line will make the jeep run rich if it is leaking or not connected. if the line is fine, then maybe that sensor is bad. also, has the o2 sensor been replaced lately?
Completely stock, and keeping it that way...
o2 has never been replaced. but it is not excessivly rich. richer than ideal for sure, but not near bad enough to make it run like it is. only light hints of black smoke when revved. rich enough to make it run like it is, this thing would look like a diesel.
1. Finish the tuneup by replacing the wires, cap, rotor.
2. 50 pounds of fuel pressure? Measured with a fuel pressure gauge? Not good! For a renix, you should have "31" psi at idle. Then disconnect the vacuum line to the fuel pressure regulator and the pressure should jump to approx. 39 psi. Be sure that the vacuum line leading to the regulator is pulling good vacuum and is not WET with fuel. If it is, you have a ruptured diaphragm in the regulator and you must replace it.
3. Here is a link to an article that can help you with testing many things on your RENIX.
yupp 50 psi. and it has a new cap/rotor just not wires. worth a shot to replace them i guess, but all tested fine. insulation is good on all, 15kv is when they blew at on the electrical insulation tester at work, which is more than a new one blew for my truck
then on to the fuel system. might check pressure with another gauge to confirm though.
checked pressure again today. 41 whiel running, pull the vacuum hose and it jumps to 49. TJwalker, i think you maybe 10PSI off on your specs, cause i looked up a new FPR and it says it regulates to 41, in that case i am spot on.
but meanwhile it seemed to run better today, took it out for half an hour or so in the snow, and other than an excessively high idle it ran great. and i believe the idle to be a bad TPS.
however, my Rad fix did not work, still has a slow leak so time for a new one.