97 XJ 4l Dual Fuel with High Idle and wont kickdown.

[Disco Damo]

Hi Folks,

It's been a while but finally I got the XJ back from the MIL.

I have a little problem though.

I was chasing an oil leak so gave the engine a good tub with my Karcher Hotmwash and all of a sudden I have idling issues and it's no longer kicking down until I'm stationary.

Computer codes are,
12 Battery Disconnect (Fitted a new Stereo recently)
14 MAP sensor (Disconnected to spray with WD after it started playing up)
24 TPS (Also Sprayed)
27 Injectors (is on duel fuel and the resistors are probably corroded on 4 of the injector wires)
27
27
27
55 End of codes

Wondering if anyone had this problem before due to MAP or TPS before or if I should be looking elswhere.

I've also adjusted the kickdown cable to have minimal slack but it doesn't seem to have made a difference.

Normally idles at about 750 to 800 but currently is up around 1500 which will be a total bitch in traffic for work.

Thanks in advance,

Damo

[LuluBelle]

is it the same on both lpg and fuel ? does it sorta seem like its flooding when starting ? I have dual fuel the lpg comes in through the throttle body it gets dirty give it a clean I use petrol and a paint brush use fine sand paper to clean the idle air control I know lpg is cheap $$ but try and a few k a week to exercise your injectors and use stale fuel up failing all that I would replace the TPS
_____ooooo
/__l_l_,\____\,___
l_---l_l__l---[ ]llllll[ ]
_.(o)_)__(o)_)--o-)_)

[Disco Damo]

Originally Posted by LuluBelle

is it the same on both lpg and fuel ? does it sorta seem like its flooding when starting ? I have dual fuel the lpg comes in through the throttle body it gets dirty give it a clean I use petrol and a paint brush use fine sand paper to clean the idle air control I know lpg is cheap $$ but try and a few k a week to exercise your injectors and use stale fuel up failing all that I would replace the TPS
_____ooooo
/__l_l_,\____\,___
l_---l_l__l---[ ]llllll[ ]
_.(o)_)__(o)_)--o-)_)

Thanks LuluBelle.

Yes same on petrol and lpg.

I've tested the TPS and it's all good but I have to get a T20 long driver to remove the IAC as I only have a little stumpy one.

I run it on Petrol to and from work once a week as well as it starts on petol all the time so that I don't think is going to be my problem.

It all started when I washed the engine bay so I'm currently looking for frayed wires and dodgey plugs which I've found a couple, restet the computer and initially it will idle at 1000 then bump back up to 1200 then about 1450.

I'm picking one up for spare parts next weekend so I can start swapping out parts to see what works and what doesn't.

The LPG wiring is not that great, so I'm going to renew all that anyway as I found a few problems with the injector emulator and the LPG ignition module dual curve interface (Ignition delay for the LPG).

Still doesn't explain the transmission issues.

I do think it could be the IAC being dirty causing the idle issue, seems to be fairly common from what I've read but the trans issue is concerning me a fair bit.

Cheers Damo

[Roler]

TPS is notoriously moisture sensitive. Did you test with analogue meter?
Not sure if spraying the MAP (cleaned it?) or TPS with WD40 is the best. MAP needs other solvent to clean.
Check for vac leaks. Clean TB with a new gasket and IAC as suggested. The not kicking down can be related to TPS as well.

[awg]

take apart and use a hair dryer on the suspected areas

I personally would not pressure wash the top of my Jeep engine

[BLAKLISTED]

Just got back from a cape trip. After a few water crossings ended up with a high idle and wouldnt shift gears untill redline. Not cool especially when paying 1.95 for ULP. Long story short i changed my 6 month old tps with my old sensor (prob oem), reset the battery. Problem solved.

I wouldnt pressure wash any engine, asking for dramas.

[Disco Damo]

Cheers folks.
I used a DIGI multi meter so no not an analogue so could only watch it change.

My issue was more that the resistance seemed to be ok but the voltage test seemed wrong.

I've just picked up a spare car which is running well so I'll change out the TPS and see what happens.

I only use WD because it's all I had at the time and being that I've mainly worked on Diesels and Landrovers in the past, I didn't realise that Jeeps were so sensitive to water which seems strange to me seems they are meant to be the ultimate 4wd.

If it turns out to be the case then some water proofing may be needed by the sound of things.

Thanks folks.