87p89lCherokee

Ok so I have a problem with starting my Jeep in the morning (Will crank but not turn over). I'm on Maui so I didn't think there would be enough of a temp difference to cause it. But anyway, my co-worker read a couple threads on some forums saying that the coolant temp sensor (Below exhaust manifold) was the culprit when nothing else worked. So I got a new one and replaced it along with all new hoses and radiator since I had to upgrade to an open system anyway. Still hard starting while cold after all that. Now what's odd is that I can get it to start a few times when pressing on the brake while trying to start. And if that won't work, I'd roll my Jeep a few feet then slam on the brakes causing my Jeep to jerk pretty good and that will start it up when just pressing the brake alone won't work. I've been told to get rid of the EGR and just plate off the exhaust hole also to replace the TPS. I wouldn't mind doing all that but I just want to change the direct cause of it instead of replace a bunch of stuff till I find the solution. Help please! Thanks (Sorry for the Long thread..)

Cherokee89sport

Try starting her in neutral
Also turn the key to the on position for a couple of minutes, then try to start her
Also check your cps

94JeepCherokeeMan

Start with a factory service manual and read up. Sounds like some weird relay/electrical problem.

87p89lCherokee

Already tried it that way. I would put her in neutral and she still wont start so I roll it a little then slam the brakes and 90% of the times viola, she starts. If not I do it again and she starts. Weird symptom

87p89lCherokee

I've been looking through my Hanes trying to find a possible solution but nothing in the cold start troubleshooting listings seem to match up

tjwalker

You have a Renix XJ (87-90) By design, the engine is not going to fire until the computer (ECU) gets a signal from the crankshaft position sensor and measures that signal to indicate that 300 rpms while cranking has been met/exceeded.

Somewhat extended crank times should be considered a “characteristic” of your engine, rather than a problem.

You can upgrade the battery and battery cables--at least 4 ga., 2 ga. better--and buy a high-torque starter.

Be sure that all grounds are good. Remove them and freshen them. You cannot tell if the grounds are electrically good by looking at them! Renix vehicles are very sensitive to ground issues.

Other than that, performing basic tune-ups on a regular basis is important, (plugs, wires, cap, rotor, fuel filter)

The above suggestions are things that will help optimize start times on a Renix engine.

87p89lCherokee

Thanks. I know that my Jeep has that "characteristic" to have a longer start than other vehicles, but when I'm holding the key for a good 10 seconds and she's still not firing up, and with the same results when trying again, I think it's a problem... Especially since it didn't do it before