Quick update:
Starting really well, wonderful in fact, 20 seconds later the idle drops.
Give it a rev for 20-30 seconds all is ok, drive to the end of the driveway, stall. Restart, all ok, drive off, very dead spot until the revs come up, then fine. Perfectly ok after that. I parked up 5 mins later and it idles really smoothly with no real pitch change at all. Driving off after that no dead spot at all, all is really well.
Just wish I could keep that smooth idle all the time.
Must be MAF related, the IACV was flithy and it idled well before I cleaned the MAF.
On idle tapping/knocking the MAF causes no change in speed.
I am hoping that the electrical cleaner I used on the MAF had just left a residue that carb cleaner and a cotton bud will remove.
Cheers
......the LHS one is in a state, but is clear within the pipe itself, but it really needs to be changed as it is perishing and collapsing.....
Happy new year all.
An update on the saga..........
I plan to hook a voltmeter to the MAF output tomorrow, but I am wondering if the IAC valve can/should be adjusted? See this link:
http://www.landyzone.co.uk/lz/f10/p38-4-6-base-idle-setting-87070.html
Page 400 on RAVE - Service repair no - 19.22.13 suggests that also.
I cleaned the valve again, checked all the leads looked ok and not resting on bare metal anywhere, lowering the risk of a bad spark. Lucas leads, I have read these are rubbish?
Latest situation is:
Start (instantly no probs everytime), it revs to about 1100 rpm then drops to 700-800 rpm (no apparent missing) then drops to stall (everytime) runs for 5-8 seconds.
Start again, the same, unless I give the gas pedal a little press, then it revs up to 1500-2000 rpm, cycles down to near stall, then again (with no extra pressure on the gas) revs again to 1500-2000 rpm, then back down the whole time it sounds like it is missing. This cycle happens for about 30 seconds or so (or until the missing stops) and I can leave the gas alone and it idles well, albeit slow 500-600 rpm.
Any thoughts most welcome to help me save some funds and while I try to find a local workshop capable........
Looks like your describing my car behaviour when it's fuel trims are way out of limit.
Go to a Testbook and reset your adaptive values, you'll have a lot of infos and resetted fuel trims.
Was the car supplied by a Land Rover specialist? I only ask because if not, I'd say it's unlikely they'll have the right gear to interogate your ECM, unless they specialise/ advertise a diagnostics service.
There must be someone on here in the area that is willing to read your fault codes and reset the long-term fuel map?
As a guide, my local diagnostics chap charges £30 for a 'scan' and has dealt with a fair amount of P38's. Kent is a little too far away from you though!
Agggggggh, I was in Kent over Christmas too. :doh:
I visit family down there often(ish).
The car came from the main Land Rover dealership in my area, so fingers crossed I can convince them to reset it as it was only bought 2.5 months ago, if not I have find somebody cheaper in the area. Let you know how it goes.
They don't know their job well. Testbook permits reset of adaptive fuel trims. I do it every 6 months.Quick update, annoyingly they said the P38s use a closed system, there are no fuel trims to reset.![]()
However they are going to give me a 1 hour free diag session next week.
Just bumped this back up as I was wondering if James ever got the problem sorted. Did resetting the adaptive values cure it?
My mechanic mate has been looking at my '99 P38 as when cold it runs like a bag of spanners - coughing splutting with revs dropping, stalling, etc for about 5 - 10 mins until warmed up. When warm, it's fine.
I did post the other day and Wammers suggested checking/cleaning the idle air control valve which we did. No change. We got a MAF sensor fault on diagnostic, borrowed another MAF and it worked lovely. However, I've just bought a new MAF and it hasn't solved it. It's still ****e!
There is the remote possibility that the replacement part is fault but unlikely. Could the problem be wiring to the MAF or does anyone have any other suggestions?