P38 4.6 rough idle + iac valve info

So after replacing the engine(thanks to my bro for the car port and help!!!) with nice new RPI one (and realising we forgot to connect the idle air control valve and the throttle position sensor) the thing wasn't ticking over very well.

Idling was very rough and it struggled a lot when on LPG.

So i took the IAC valve off and cleaned it with a electrical contact cleaner and a clean cloth. FYI it seems that the moving bit inside the IACV feels very loose when its working properly.

Then reset the adaptive values of the ECU (and cleared 2 IAC faults with a faultmate msv2)and now it's idling very nicely.

LPG is still a little knobbly but i think i need to take it to the guy that installed it so he can remap the LPG ECU??

Just thought I’d share that with people in case it’s helpful

(The thing that made me notice we forgot to connect the TP sensor and IAC valve was a persistent gearbox fault (no MIL lamp, no gear selection info on dash. This is limp home mode I believe) very rough running and very poor fuel consumption.

If anyone has any questions let me know and I’ll see if i can help. J

the guy next to me at work likes his RAV4 coz it never breaks down. i say thats no fun!!

rav 4, is that some kind of soup?

the lpg kit can be set up yourself if you have the software and lead, what make/model is it?

you can get a multiple lpg kit interface off ebay or on the web for about 60 quid, youve spent a fair bit of time and cash already so a few more quid won't hurt and you will be able to keep a close eye on the lpg side of things!

gavbriggs said:

rav 4, is that some kind of soup?

the lpg kit can be set up yourself if you have the software and lead, what make/model is it?

you can get a multiple lpg kit interface off ebay or on the web for about 60 quid, youve spent a fair bit of time and cash already so a few more quid won't hurt and you will be able to keep a close eye on the lpg side of things!

Click to expand...

ah i'm not sure. the guy did tell me.give me some clues and i should be able to remember/find out!

i definatly want to get such a kit but seeing as he said he wants to do a free check up within a year i think i'll take him up on that offer!

the thing is, most (but certainly not all) lpg specialists set the lpg up on the lean side, this makes em run hotter and can lead to issues,

setting it up slightly rich keeps it cooler and can avoid engine damage. you get a little less mpg but its certainly cheaper than a new engine!

it took me a while to get used to my setup but now i know it fairly well i can jiggle it to keep it running sweet and there really is no difference on lpg for most of the time. i have noticed that ive had to up the gas a little due to the cold (i was told that companies change the mixture of the lpg during winter, not verified this but it could explain me having to tweek mine???)

does the software come with the cable?

where did you get yours from? i've seen RPI have one. maybe they'll give me a deal seeing as i bought an enigine from them a couple of weeks ago...

i guess if i can dig out the LPG ECU it will say what make/model it is on it somewhere?

thanks