XJ running badly.

[East-Gippsland-XJCherokee]

Originally Posted by LuluBelle

YOU GOT SHOPS!!...............everything on my XJ was purchased online
I Know the Feeling!
Hope the new gear sorts it for you
In the middle of no where a broken XJ in the yard and sweating on the Australia Post Parcel delivery Lady (Subcontractor)................................... ....................For Needed Parts Gotta love the country ............But would never move back to the City

Yeah there are shops in town, but besides they charge way to much, their staff has no brain cell amongst them! I bought a battery from Supercheapauto, it failed under warranty, so thought I be just fine! WRONG, besides being treated like a common criminal due to their lack of customer service, dealing with their ME generation staff was testing! It took them over a week to replace the faulty battery that was under warranty and could not drive my XJ, hence I will never spent a single cent in their shop again. Repco is somewhat better, but most times they don't have what I need, than they tell me the time to get it in and the cost! Glad I have a strong heart as their pricing is of this planet, hence Evilbay gets my vote.

I am sure I will solve this mystery, but the XJ is becoming more like the ex wife, was great when things were good, but in the long run it cost me an arm and a leg!

[rustynuts]

Missing when cold leads me to think ignition. It is harder to fire a cold cylinder than a hot one.

[East-Gippsland-XJCherokee]

Originally Posted by awg

If it ONLY misses under load, but will free rev otherwise, I was taught (on tricky to tune multi-carb cars) that points towards a fuel/air issue

vehicles controlled by multi-electronic sensors are not my forte, even though I am qualified in Electronics, but I know dud sensors can cause weird problems.

have u double checked the integrity of all vacuum hoses?

Yeah I agree, and I checked every single hose besides every single vacuum hose. Took off what I could to have a closer look and cleaned everything. Have also got the WD40 out a few times, under idle or with higher revs spray the sh#t out of everything to see if revs go up or down indicating a vacuum leak, none found as yet. The only leak is an exhaust leak around the headers/extractors, but only very marginal and has been there the day I bought it (2 years ago).

I also cleaned the throttle body, pulled the 2 sensors cleaned them but made no difference, but I did replace the IAC 12 months ago, and have replacements coming for the other 2 sensors.

I still have my money on a sensor of some sort playing up, when its cold it plays up real bad, warms up and makes better contact or operation is better, plugs can still be the culprit and also the same for the O2 sensor. I think the plugs will be in tomorrow, so besides a new fuel filter, new plugs should go in as well.

Will post my findings.

[East-Gippsland-XJCherokee]

Originally Posted by rustynuts

Missing when cold leads me to think ignition. It is harder to fire a cold cylinder than a hot one.

New plugs should be here tomorrow, and that might solve this problem.

[East-Gippsland-XJCherokee]

Just want to revamp/refresh this problem some what. Last week was when my XJ was the worst with this problem, whilst on my way to pick up my new Rubi's the problem got this bad,

Loss of at least 50% of power
Would not go past 2500 revs whilst driving
Put the pedal to the floor and it was like there was a stop on the throttle when it hit 2500 revs
At some stage when I floored it, it backfire really loud, way way worse than missing

Now I made it to the next major town, and seeing the tank was 1/2 empty I filled it with V power, previous fuel was 95 ron, and pretty much all the problems above stopped when I got out of the servo, although that lasted a few hours of driving as it did go back to lack of power, but only a loss of around 25%, no back firing just stutters and misses.

As much as it runs OK now, idles perfect, starts well, but as soon as you load it up whilst driving the miss will start around 2500 revs, but goes when it warms up, and only misses so once a while and tends to do that around 4000 revs. I still think it is somewhat down on power but maybe at most 10% or so.

The dirty fuel thing was something I thought about, but I am on my 3rd V power tank now, surely if it was that it would have pasted by now.

[rustynuts]

Originally Posted by East-Gippsland-XJCherokee

Just want to revamp/refresh this problem some what. Last week was when my XJ was the worst with this problem, whilst on my way to pick up my new Rubi's the problem got this bad,

Loss of at least 50% of power
Would not go past 2500 revs whilst driving
Put the pedal to the floor and it was like there was a stop on the throttle when it hit 2500 revs
At some stage when I floored it, it backfire really loud, way way worse than missing

Now I made it to the next major town, and seeing the tank was 1/2 empty I filled it with V power, previous fuel was 95 ron, and pretty much all the problems above stopped when I got out of the servo, although that lasted a few hours of driving as it did go back to lack of power, but only a loss of around 25%, no back firing just stutters and misses.

As much as it runs OK now, idles perfect, starts well, but as soon as you load it up whilst driving the miss will start around 2500 revs, but goes when it warms up, and only misses so once a while and tends to do that around 4000 revs. I still think it is somewhat down on power but maybe at most 10% or so.

The dirty fuel thing was something I thought about, but I am on my 3rd V power tank now, surely if it was that it would have pasted by now.

MMM OK. Food for thought. Bad fuel can be bad for plugs.
I would take it for a full on fang and then run a scanner over it, but that is just me.

[East-Gippsland-XJCherokee]

Originally Posted by rustynuts

MMM OK. Food for thought. Bad fuel can be bad for plugs.
I would take it for a full on fang and then run a scanner over it, but that is just me.

Full on fang! Man I am on 3rd tank of V power @ 1.40 a litre, all due to me fanging the funk out of it LOL The scanner testy thing I bought with the help of members on here last year, never ever worked, sure it came on when plugged into the XJ, but never could find a connection to the ECU, hence the key dance is the best I can do, the only error code I have had whilst this gremlin is doing my head in, is the O2 sensor code, and thats due to me disconnecting it to see how it fangs, and that error code is there now due to the picket fence mod I did

My very first take on this gremlin was bad fuel, as this problem all started after I filled up ready to go and pick up my Rubi's, it might have done a spark plug due to bad fuel, and hopefully that possibility will be tackled when the plugs come in tomorrow.

I really would like to solve this problem, not just cause I want to go bush camping/hunting/fishing, but hopefully it might help some one else on here that has the same symptoms.