Hello. Can anyone tell me what the resistance should across the five injectors on a Td5 P10 engine. I have a new Disco 2 project that is running like a bag of nails, I checked it this morning and am getting (ohms) 1.4, 2.1, 2.2, 2.0, 1.3 !. I thought maybe number 1 and 5 were dodgy and also noticed injector 1 is a green top while the others are all black tops !!! I bought a second hand blacktop injector from ebay and it reads 1.4 ohms impedance which doesn't really help ! Any advice on resistance or on the green top (which I didn't think was interchangeable) appreciated.
Mark Ormond
Active Member
I have just done a search of RAVE both electrical and mech and cant find any readings.
But from memory mine read 1.2 all 5 dont take that as gospel
But from memory mine read 1.2 all 5 dont take that as gospel
markomate2
Well-Known Member
Hi Not sure what checking the coil impedance is going to tell you.
But you could contact Merlin Diesels or Diesel Bob, both should be able to give you some advice.
If you really want to know what your injectors are up to, have them tested, it costs about £30 per injector.
Mark
But you could contact Merlin Diesels or Diesel Bob, both should be able to give you some advice.
If you really want to know what your injectors are up to, have them tested, it costs about £30 per injector.
Mark
markomate2
Well-Known Member
Yes I thought the poll was a bit "random"!
Thanks for the answers lads. Firstly let me explain my situation re injectors. I have a 1998 engine that was running fine 14 months ago. I know the engine has been well serviced to this point and even though 250k miles it has good compression. Unfortunately there was no security where the car was parked and several people had access. When I went to collect it someone had removed various parts from the car including rocker cover. There is the possibility someone has swapped injectors but that's another story. Anyways I trailered the car away and re-fitted rocker cover/gasket, clean fuel, filter etc but its hardly starting and now seems to be missing on two cylinders. There are 4 black top injectors and 1 green one in there ! Various sites say you cannot interchange these injectors i.e black and green , is this the case ? Also various forums say it is possible to identify fault injector by impedance test hence I've been researching this re Disco 2 but cannot get a definitive answer. Like I say in my original post I have 2 injectors (no 1 & 5 a black and a green !) reading 1.4 and 1.3 ohms and the middle 3 injectors (black) read over the 2.0 ohms. I bought a black top on ebay which reads 1.4 ohms ! Regardless I would have thought there would be consistency and is the green not a different type of injector ??.
Re my random poll lol. Yes very random I agree , I'm unfamiliar with the site and didn't realise it was pegged onto this ! I have a Disco 2 and a Mk1 RS Focus and think they are both future classics. I'm glad to say I don't have a MX5 I only put that there as a third choice because my young nephew swears there then best car ever made !
Re my random poll lol. Yes very random I agree , I'm unfamiliar with the site and didn't realise it was pegged onto this ! I have a Disco 2 and a Mk1 RS Focus and think they are both future classics. I'm glad to say I don't have a MX5 I only put that there as a third choice because my young nephew swears there then best car ever made !
Landmark2
Well-Known Member
Hi, If you can find someone with Nanocom Evo or similar they will be able to read the injector serial numbers. They are all different and need to be programmed into the ECU to run properly. So if any have been swopped you'll soon find out. The serial numbers are on top of the injectors.
HTH,
Griff
HTH,
Griff
markomate2
Well-Known Member
Hi
You def should not have a mix of injectors, the black, older ones operate at a lower pressure than the later, green ones.
Sounds like it had issues and someone tried to "fix" it.
IMO the best way forward is to know where you are with the injectors, get them properly tested, see if the test company will take all five and tell them that one is green, they may be able to exchange it for a black one.
Also check if it should have green or black ones.
According to RAVE the rocker shaft is different for black and green ones.
Until you know that all your injectors are ok you will be chasing around looking for faults, sorry to press the point but Ive done the same thing.
Mark
PS Disco 2 followed by MX5, never been into Fords!
You def should not have a mix of injectors, the black, older ones operate at a lower pressure than the later, green ones.
Sounds like it had issues and someone tried to "fix" it.
IMO the best way forward is to know where you are with the injectors, get them properly tested, see if the test company will take all five and tell them that one is green, they may be able to exchange it for a black one.
Also check if it should have green or black ones.
According to RAVE the rocker shaft is different for black and green ones.
Until you know that all your injectors are ok you will be chasing around looking for faults, sorry to press the point but Ive done the same thing.
Mark
PS Disco 2 followed by MX5, never been into Fords!
lol, thanks Griff and Mark, it looks like the green injector is a swap, someone who should have not been near the rocker cover and who would know this started talking some gibberish about "injector 1" when I turned up to collect the vehicle and I think they thought I had forgotten about the car and were using it as a donor, when I turned up they looked very pale ! The nuts holding the injectors down onto rocker shaft were on about hand tight ! Griff I know a man who can do this and will be seeing him to check, I,m hoping its only the green one though that's the problem !!!!!
Ill keep you posted...................
Ill keep you posted...................
markomate2
Well-Known Member
Does your guy have something like a Hartridge tester?
Ideally you are looking to get a full printout for each injector, it will cover the full test cycle.
To give some background, I had mine checked by a well known diesel man, 3 were "leaky" but I didnt get to see the test reports, I asked for all five to be refurbished.
When I re-installed them, the car started ok, after a few purges, then started missing and putting out unburnt diesel (white smoke)
I took all the injectors out again, and sent them to Merlin Diesels (not connected to them in anyway!)
Merlin, said 4 had passed, 1 had failed "badly", got an exchange replacement from them, with a test report.
Total cost £ £350 ish, + £400 ish for the first lot of testing/work.
When I got the injectors back each one was complete with a full test report.
All refitted, ran great, even without recoding, now been re-coded and she runs very sweetly!
Hope above helps, just dont want to see anyone else waste their time/money on substandard repairs!
Mark
PS when you re-install the injectors, follow the advice on here and on Discovery2 website, make sure everything is clean and be careful when you tighten down the rocker shaft bolts, a few threads on here about broken ones, just buy new ones and use a good torque wrench.
Ideally you are looking to get a full printout for each injector, it will cover the full test cycle.
To give some background, I had mine checked by a well known diesel man, 3 were "leaky" but I didnt get to see the test reports, I asked for all five to be refurbished.
When I re-installed them, the car started ok, after a few purges, then started missing and putting out unburnt diesel (white smoke)
I took all the injectors out again, and sent them to Merlin Diesels (not connected to them in anyway!)
Merlin, said 4 had passed, 1 had failed "badly", got an exchange replacement from them, with a test report.
Total cost £ £350 ish, + £400 ish for the first lot of testing/work.
When I got the injectors back each one was complete with a full test report.
All refitted, ran great, even without recoding, now been re-coded and she runs very sweetly!
Hope above helps, just dont want to see anyone else waste their time/money on substandard repairs!
Mark
PS when you re-install the injectors, follow the advice on here and on Discovery2 website, make sure everything is clean and be careful when you tighten down the rocker shaft bolts, a few threads on here about broken ones, just buy new ones and use a good torque wrench.
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