Birty Dastards Jeep Club

Tech Forum => Workshop => Topic started by: JamesH on July 29, 2015, 09:46:41 AM

Title: Engine problems - help please
Post by: JamesH on July 29, 2015, 09:46:41 AM
I've just taken the XJ out for a test drive before 7S at the weekend and it was bucking like a bronco and actually stalled on me. I've changed throttle position sensor cos I had one to hand but it made no difference. Tried unplugging O2 sensor, nothing changed. Checked fuel pressure, fine. Took out again for a blast through just in case it was that and got a check engine light. Smells really rich and had some light black smoke when revved on drive (neighbours love me right now).

Have run out of time before work now.  Any ideas where to start?
Title: Re: Engine problems - help please
Post by: Lornaben on July 29, 2015, 02:14:00 PM
Air intake plumbing / air filter ???

A wild guess based on it running very rich.
Title: Re: Engine problems - help please
Post by: daggie on July 29, 2015, 07:02:58 PM
10 bob its the cam position sensor, in the dissy !
had this happen to the tj
Title: Re: Engine problems - help please
Post by: JamesH on July 29, 2015, 07:24:27 PM
Dropped it into TCJ this afternoon. A quick scan in the car park showed MAP and O2 sensor codes, hopefully they can get it sorted in the morning. I have so much crap to get done that I had to just hand it over to someone else. Fingers crossed I'll come back with the fix tomorrow.
Title: Re: Engine problems - help please
Post by: Dave69 on July 29, 2015, 07:57:27 PM
buy a diesel as we all know how they fail
Title: Re: Engine problems - help please
Post by: JamesH on July 30, 2015, 05:50:48 PM
New MAP sensor fitted, codes cleared and all is good in the world.

TCJ haven't really known MAP sensors to fail before but from memory I changed this before when I was fighting problems that turned out to be the fuel pump so it could be that only the cheapo sensors fail.

If it helps anyone else the symptoms were: really rich running, rough running, spluttering power loss / drop off. Started out very occasionally and a throttle blip would seemingly sort it, sometimes was at idle, sometimes not. Would occasionally drive ok but a little rough but the sort of thing easily ignored. When finally went it was rough as F, actually stalling when stopping but could just about be driven. Codes came up for O2 sensor shorted to voltage and no 5v to MAP sensor, I thought this meant wiring issues but changing the MAP sensor fixed it.

 :icon_biggrin:
Title: Re: Engine problems - help please
Post by: gazjeep on August 01, 2015, 11:23:00 AM
Had similar on the TJ twice, both times TPS & O2 sensors changed & fingers crossed it cures it

Didn't have check engine but other than that symptoms very similar

Have a great time at SS
Title: Re: Engine problems - help please
Post by: Dave69 on August 01, 2015, 08:53:32 PM
i think this thread can now be closed
Title: Re: Engine problems - help please
Post by: JamesH on August 01, 2015, 09:10:28 PM
Got a good MAP sensor for sale  :lol_hitting: