Diesel Hot Starting Fault P38

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It should not change anything apart from hot start fault so i would go back and check you have it wired up right as something is wrong,tiga
 
Hi, Can I just check Tiga, that the resistor goes across the normaly closed contacts on the relay. My relay I found in the shed isnt marked up as you describe, but is 5 pin.

Thanks
 
hi,again.i checked all the wiring, it looked ok, the only thing i noticed was the legs of the resister where touching , must have been when i taped up when id finished. i pulled them apart and tried it again, still the same, tick over too high. could i have blown the resistor or somthing? no knowledge of car electrics at all.
 
Hi Gents,

Reading the comment on the high tick over - I Reckon the problem lies with the relay wiring - as the resistor must be permanently in the circuit and not being switched out once the engine is running.

If you take the feed from the white/red trace wires they are ignition live feeds the relay will be energised all the time unless you use a timer relay (either an adjstable as I did or the heater plug relay from a diesel Escort - available in many Breakers yards) which will deenergise after its set time.

A non timed relay must be fed strictly as per Tigapiglets original spec.

Tigapiglets mod has made my Rangie start perfectly every time, I changed it only in as much as I used a programmable timed relay.

Hope this helps

Cheers

Julian
 
Can anyone tell me if the resistor goes across the normally open or the normaly closed contacts on the relay? I am itchinf to carry out this mod on my pals P38.
 
Normally closed - so that when the relay is energised and the contacts open the connection is forced through the resistor and not the closed contacts
 
hi tigapiglet ive got p38 same problem when hot sod to start if you could email me drawing or diagram for this relay would appreciate also have a problem with tickover some time feels like the engine is missing abit eny clues
 
HI all, I have the same starting problem on my 97 dse, I have a little problem with this mod and would be grateful if someone could explain…
I have checked pin 30 on the glow plug relay, this pin is permanently live, therefore the 2k resistor is in series with the temp sensor permanently, meaning the ecu will “think” the engine is always colder than it actually is. In my view this mod will only work correctly if (as prev stated in another post) a timer is used to control this cct.
Has anyone actually found the route of the problem i.e. why a high mileage dse develops this problem in the first place?
Cheers in advance
 
Hi all
I did the modification as described and as I suspected the relay was energized all the time the ignition was switched on, which in my opinion defeats the object of this mod. The glow plugs did engage every time the rangie was started even when hot, but I had the same problem as mick2444, she ticked over a little higher than normal, I also noticed another problem, gear changes were at different rpm and she was also a lot heavier on fuel, my guess is that the fueling map is totally different when engine is cold (which this mod makes the ecu “think”), it must also alter gearbox map.
To get around this, I have taken the design principle of this mod one step further and built a simple timer/relay based on monostable 555 cct. which puts the 2k resistor in series with the temp sender for about 30 seconds. The relay then goes short giving the ecu the correct temp resistance value.
Since installing, the car now starts perfect every time, and when the timer cuts out, the tick over drops back to what it was before the mod was installed, gearbox is also back to normal. (I can’t comment on fuel economy as only installed a couple of days ago, but I’m sure that is also back to normal)
I can only speak for my model rangie (97 dse), but in my view this mod is pointless unless a timer is installed, you may as well ditch the relay altogether and just put a 2k resistor in series with temp sender as this would have the same effect.
If any one is interested I can supply cct diagram for timer (mail me), it’s very simple to build (took about 45min), all parts are available from maplin, all parts cost around £10, this included a relay as the land rover one YWB10032L is not suitable as a 555 timer will not supply enough current to power it, unless a transistor is added which would make cct more complicated than it needed to be.

Neil
 
Hi Neil, buy not hot starting do you mean that it takes about 5 seconds of turning over the engine to start? or do you mean forever so to speak? Mine starts from cold immediatly but as i say five seconds of turning over when hot.

Thanks
Alan
 
Hi bigal
Yes that right their seems to be an inherent problem with the dse, starting when the engine is warm, basically the glow pugs do not operate ounce the engine is a little warm needing lots of cranking to get the engine started, with mine it just depends on how warm the engine is, if ive only done half a mile or so from cold, stop the engine then try to start again she a pig to start, when she does finally fire up usually greeted by a nice cloud of smoke, on the other hand if I have done a good few miles and the engine is fully warm, she’s not to bad to restart.
 
Hi, I have read all messages regarding this matter and am no closer to sorting this problem with my Rangie out. The problem I am having is when the Rangie is started from hot or cold it is really slow to turn over. I am wondering if this is associated with the same things you all have discussed?
 
Hi there had51
No this thread is not associated with the problems you are having, this thread relates glow plugs not operating when engine is warm, I’m no mechanic but I suspect you have a battery or starter motor issue.
Good luck
 
Cheers neildeb0...I cant think that the battery is past its best as she does turn over without hesitation. I have had the glow plugs inspected on her last service to which I was informed that they were in order. You know how it is, take your motor for a service and the problem does`nt arise until you leave!
My Rangie is turning over but takes some time to start, I wonder if this problem is a fuel pump problem?...If anyone has got any other ideas out there, please let me know, cheers.
 
Had , I wish i could help you but your discription of the fault is a little short on detail.
To be of help , tell us at what point the problems occur.
1. is it a problem all the time
2.Cold start probs?
3.Hot start probs?
4.Does a jump start help
5.have the battery tested
6.Have the alternator tested
7.Try starting with the door open(air sus off)
etc etc
let me know how u get on
 
Hiya REMETECH, thanks for getting back to me.
Just a few answers to your questions. I am having problems whenever I try and start my Rangie from cold or hot, even when I nip into the shops for a loaf of bread!
The problem is only when I turn her over and it usually takes around 30 secs or so for her to fire up.
I have had no need to jump start her as like I said she does start with some difficulty.
I will give some of the things you have suggested a go!
Once again I really do appreciate your help, many thanks.

Just checked battery and all seems fine, therefore I can only assume the alternator is operating as it should?...
 
had,
First thing dont keep cranking your engine to get it started. It kills the batteries. i should know ive killed two on mine , and they dont come cheap. How have you tested the battery ? has it been discharge tested?
Do the glow plugs , yellow light come on then go off to assist starting.
With mine if the glow plugs didnt come on or the battery was poor i had your symptoms.
If when your having your problem try and get someone with a big van(large cap battery) 130 amp and ask them for a jump start . see what happens .
My gut feeling is you have a problem with the heater plugs or associated electronics.
Costco do a good bosch battery that mine has run on really well and its only about £45. I would start by putting a fresh battery on.But dont keep cranking on it if it doesnt sort it!!
 
REMETECH

Hiya matey, I`ve tested my battery today with the aid of a voltmeter.
The result is a well charged battery showing 12.8v which only leads me to believe there is no problem with the alternator also.

I am going to try fitting some quality glow plugs as this has been mentioned to me on several occasions now. Thanks for your good advice and I will let you know how it goes.

Until then, many thanks!

Sorry mate, forgot to mention...the glow plug light does come on and then go off...mean anything to you?
 
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