Advise needed - Engine keeps missing and very jecrky

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.

@Hoveedge

Member
Posts
37
Location
Brighouse
Hi all, really need help with this one now, I have a 53 plate Freelander 1 TD4 with 130K on the clock. My wife reported that the car keeps surging and hesitating so did a service and changed all the filters including fuel filter in wheel arch. Thinking it might of picked up a bit of dirt I removed HP pump, stripped it down and replaced every o ring seal ect. Rebuilt test drove more power but still this jerking about and hesitation it now keeps cutting out when stationary. Put vehicle on diagnostics it brought up the rail sensor, changed this and replaced fuel pump in wheel arch. Took out sender unit in fuel tank looking for possible blocked fuel lines in the process. All seems ok. Took Freelander on a test drive and went down motorway for a couple of junctions, running better then ever regarding power but the hesitation cutting out is still there engine management light flickers on and off, does not seem to stall anymore when stationary. Lost for ideas could it be an injector don't really want to keep ordering parts to still have the same problem. Input very much appreciated
 
Hi I have inspected the harness I does look like it might of been replaced at some stage as the pressure sensor goes to a plug which inturn is plugged into a little grey box I've googled it and it seems to be a tuning chip. Do these go faulty??
 
What colour is the rail sensor plug, green or black?
What's the make of the timing box?
Hi its a black sensor, I will take photo of the grey tuning box It does not appear to have a make stamped on it but does have a V logo on it will take photo in half hour and post. thank
 
20180122_122701.jpg 20180122_122708.jpg 20180122_122701.jpg 20180122_122716.jpg 20180122_122944.jpg
 
Hi There what Nodge is asking is the plug connector green or black that goes to the sensor in your photo, also you could try spraying some electrical contact cleaner into the plug and push it on and off a couple of times, see what that does also maybe remove the trick box as it maybe faulty, you can always replace it if it is not that.
Hi if I unplug the trick box will I need to plug that socket into something else or put a standard wiring loom on to the sensor.
 
Hi if I unplug the trick box will I need to plug that socket into something else or put a standard wiring loom on to the sensor.

If you trail back the trick box it should at some stage fork off and join up with the original loom lead to the MAF sensor, they do usually and you would need to unplug it from the trick box and plug back into the MAF direct, it could be a injector playing up and a leak back test would help, but trying the plug to the fuel senor and trick box stuff would be the easier of the two at the moment I would think.
 
Does anyone think it might be an injector fail. So far I have not done a leak test
Before a leak test just pull the leci plug on each injector in turn on tickover and note if there is any change. I had a totally blocked injector around the same miles and if it is an injector have a go at stipping it and cleaning the hole out where the tip pockes through. Put yer best reading speks on as theres a very tiny shim in there ;) worked for me. If you nack it nowt lost:)
 
I would delete that unknown box - always suspicious when a manufacturer is not proud enough of their product to put their name on it.

Trace its loom - it might just be a simple MAF bias.
 
If its wired to the fuel pressure sensor, is it not telling the ECU there is less pressure so it opens the injectors longer?

Depends what else is wired through it I suppose.

Hopefully no wires were broken when that was installed, ie existing connectors were used and that plugged in the middle, but I wonder if there are bits now missing, eg to the fuel pressure sensor? Is there another connector laying around the sensor that's not plugged in?

I can't believe that rusted connector (looks like something you'd have indoors on your computer!) is original.
 
If its wired to the fuel pressure sensor, is it not telling the ECU there is less pressure so it opens the injectors longer?

Depends what else is wired through it I suppose.

Hopefully no wires were broken when that was installed, ie existing connectors were used and that plugged in the middle, but I wonder if there are bits now missing, eg to the fuel pressure sensor? Is there another connector laying around the sensor that's not plugged in?

I can't believe that rusted connector (looks like something you'd have indoors on your computer!) is original.
You can find them on ebay - Racechip tuning. They have two plugs, and that parallel plug into the box does look like the one supplied!

There’s no telling what that box is doing as it might have failed internally.
 
Looking at the wiring it goes from the rail sensor to a MAF sensor and tees off to the tuning box, I will try unplugging it and see what happens.
 
If its wired to the fuel pressure sensor, is it not telling the ECU there is less pressure so it opens the injectors longer?

Depends what else is wired through it I suppose.

Hopefully no wires were broken when that was installed, ie existing connectors were used and that plugged in the middle, but I wonder if there are bits now missing, eg to the fuel pressure sensor? Is there another connector laying around the sensor that's not plugged in?

I can't believe that rusted connector (looks like something you'd have indoors on your computer!) is original.
I think this has just been teed off the boost sensor has been disconnected and the vacuum pipe to EGR has been blanked off, EGR Valve still on vehicle which I am going to by pass. Its been running ok bit gutless when pulling weight but ran it for a year no major problems. This has been the biggest job by far, just wish I could find the cause. Will try what you have said and post outcome.
 
Back
Top