I had read a few other forms about this I just wanted to see what everyone thought about my exact situation. I’m on vacation now so I can’t test anything ( also can’t get it off my mind) but I was driving my Jeep the other day when I got to a red light the engine just shut off. Tried to start it back up and it turns over good. It will do it again and again. When I put the key in I can hear the fuel pump engage and on the fuel rail I pushed the little nipple and pressurized fuel came out. That must mean it’s the spark right? All the spark plugs are 6 months old. Leads me to think it’s either the distributor or the ignition coil. I ordered both to replace when I get back just wanted to know if you guys have any other ideas as to what it could be?
Engine shut off when at red light the other day
- Thread starter Tycarver
- Start date
Rubicon John
TJ Enthusiast
It's normal,
Older version of "START / STOP " gas saving technology
Older version of "START / STOP " gas saving technology
Forgot to mention there’s no check engine light. That and the IAC should throw a code if I’m not mistaken?
Sometimes, sometimes not. I had a dirty IAC that was causing problems and it never threw a code. And the crankshaft sensor can often malfunction without a code.
It was idling really good before crankshaft I might go ahead and order be worth it to grab the IAC also?
Since you have checked the fuel, I would next check the distributor and rotor (you never mentioned the year/engine), and ensure you are getting spark. If you are getting both spark and fuel, then I would pick up an inexpensive OBDII scan tool and plug it in and do a scan. Look up any codes. Likely to be the crankshaft position sensor as mentioned by Bromel or the distributor position sensor (it's a plate located inside the distributor).
When was the last time you bought gas? Could be a bad tankfull? Or the gas cap on wrong? Did it eventually start up or did it only crank over? Fuel pressure could still be low even if it squirts out of the Schrader valve. Put a gauge on the rail to be sure you have enough pressure. Everybody that has a vehicle 1996 and newer should have at least a basic OBD2 reader.
I actully broke down right next to a gas station pushed the Jeep in there and got half a tank of gas...still never started up. ( I do have a obd2 scanner)
I did check the obdII port there was no codes. I have the 4.0 inline 6 I went ahead and orderedthe crankshaft position sensor and the distributor.
I changed the crankshaft position sensor no luck. Got a spark plug tester and it has spark and I spray starting fluid in the throttle body still does not try to start it just turns over and over. I’m stumped.
I was able to get it to start lots of starter fluid and shifting the transmission back and forth before trying (since it died in gear) it started I ran it on idle for about 5 minutes and it was doing good then I put it in drive right when I put it in drive it died. And I have yet to be able to start it back up.
I'm pretty sure an auto has something similar to a neutral safety switch to prevent starting the engine in drive. Its possible that you are getting a signal that triggers the engine to shut down. This is just a guess. Or you have a possible coil issue that is getting hot which caus8the coil to short out. Again, just a guess.
right now i can’t even get it to start i keep trying to slam it back and forth between drive and park to reset it
Another few hours of trouble shooting and now I’m not getting spark. Compression test all came back around 150 on all Cylinders so good there. Not getting spark now so moving on to electrical is there something I need to do to like “unlock” the engine maybe?
Shade tree way is to pull the battery cables and turn the headlights on to use up any stored energy, headlights off, and get to work.
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