Rover V8 EFI wont run pulling my hair out now!!!

Rover V8 EFI wont run pulling my hair out now!!!

Author
Discussion

jensencars

Original Poster:

66 posts

72 months

Monday 12th March 2018
quotequote all
Globs said:
Good question, answered by some ez-start smile
hi,
will it run on easy start or just fire I ask because it is firing/popping now will have to get some

jensencars

Original Poster:

66 posts

72 months

Tuesday 13th March 2018
quotequote all
update on yesterday!!!!!
right after stripping off timing chest and finding all in order I have today removed sump due to water going in from timing case and gasket torn I thought the oil smelt petrol it was new oil last week. re-assembled most bits have not put rad back in yet for easier access, checked and re - checked timing I am in the region of 12 degrees to TDC with dizzy loose, new oil try again cranked over and its trying to fire but wont pick up smelt plenum /AFM intake can smell petrol remove number 1 plug definitely petrol on it not sure if its to much or not !!
I then think I will go back through the fuel injection test as laid out in the manual all is going fine until I get to test7 injector test (resistance check) I carry out test with ECU unplugged ignition off connect ohmmeter to pin14 on ECU plug and pin 87 on main relay I get open circuit 000 on meter - It should be 7-10K I then check all the other 7 injectors ,,,,, all the same, if I unplug injectors as test said it goes back to infinity 1 on the screen , is it logical that all 8 injector windings have gone down or should I be looking at something else, I'm sure they was within range last time I tested only difference I have purchased a decent meter and replaced main relay.
would this be my problem any ideas gratefully received this is my first experience with EFI

Globs

13,841 posts

230 months

Tuesday 13th March 2018
quotequote all
jensencars said:
hi,
will it run on easy start or just fire I ask because it is firing/popping now will have to get some
Yes, it will start, run nicely for a few seconds and then stop, but you can carry on spraying it in to keep it running.
I once had a VW beetle that had a large float-chamber full of dead petrol and no way to drain it so I ran it for about 2 minutes on ez-start until the fresh petrol got through. It was fine on it's own from then on.

Don't use ez-start on diesels BTW, however tempting, but it's fine for petrol engines.

SLB

255 posts

240 months

Tuesday 13th March 2018
quotequote all
Sounds like you could be onto something, but if not it could be worth checking the ignition amplifier. I have an 88 350i and converted mine from 2 pin to 3 pin a while back after an amp failure. Some of your symptoms seem similar to mine when the amp was failing but that was only when the engine was warm. Could be worth checking the amp wiring was changed correctly and then swap the amp for a new one as my first cheap 3 pin one latest about a year before failing again. Good luck, Steve.

KKson

3,395 posts

124 months

Tuesday 13th March 2018
quotequote all
SLB said:
Sounds like you could be onto something, but if not it could be worth checking the ignition amplifier. I have an 88 350i and converted mine from 2 pin to 3 pin a while back after an amp failure. Some of your symptoms seem similar to mine when the amp was failing but that was only when the engine was warm. Could be worth checking the amp wiring was changed correctly and then swap the amp for a new one as my first cheap 3 pin one latest about a year before failing again. Good luck, Steve.
I've had a total of three ignition amps fail over the last few years however the give away was the weak feeble spark. If you've got a big blue healthy spark, capable of jumping 3 or 4mm then I doubt it's the ignition amp. I now always carry a set of the spark detectors. if the ignition amp fails there's a small glimmer of life in the detector but when healthy it's a very bright and obvious flash.

https://www.ebay.co.uk/itm/Laser-2780-Ht-Lead-Igni...

Oneball

842 posts

86 months

Tuesday 13th March 2018
quotequote all
Have you got the ohmmeter on the right setting? Injector resistance is usually around 10 ohms not 10,000 ohms

I’m not familiar with the Range Rover’s ECU plug but by measuring the resistance between what I’m assuming is the injector’s pin on the ECU plug and the relay you are just measuring the resistance of the injector, you can do this at the injector itself by removing its plug and directly connecting to the injector.

I wouldn’t have thought all 8 were duff so maybe there is a wiring issue.

As others have suggested the easy start test will verify whether it’s a fuel issue very simply.

You do appear to have fuel and spark, have you got oxygen?

jensencars

Original Poster:

66 posts

72 months

Tuesday 13th March 2018
quotequote all
thanks all..
yes I prob have the ohmmeter on the wrong setting I had it on 20K as the book said 7-10k, will put it down to 200
the other thing that confuses me is reading that the voltage gets dropped from 12v to 3volt at the resistor pack my resistor pack checks out on the resistance side of 6ohms on each terminal from the 12volt feed but I get 12volt in with ignition on and 12 volt out to each injector and 12 volt at each injector plug

KKson

3,395 posts

124 months

Tuesday 13th March 2018
quotequote all
I've tested my injectors previously and only put 3 volt to them. I think you might have found your problem? Have they been fried due to the resistor pack not dropping the voltage down to 3?? There's some very useful info here:

http://www.vintagemodelairplane.com/pages/Download...

jensencars

Original Poster:

66 posts

72 months

Tuesday 13th March 2018
quotequote all
hi
yes thanks that's where I tested from but the resistance check was right but I still get 12 volt out will have to get into it to see whats occurs in there

Penelope Stopit

11,209 posts

108 months

Wednesday 14th March 2018
quotequote all
If you are measuring the voltages at the resistor packs or injectors you must ensure that they are connected to their circuits, the circuits must be complete when you measure for voltage values.

Measuring for voltage values along open circuits like disconnected injectors, relays or resistor packs will not give you the voltages that you are looking for, there are no volt drops across resistors that don't have current flowing through them

In summary - Resistors only drop the voltages in complete circuits as they need current flowing through them to do this

KKson

3,395 posts

124 months

Wednesday 14th March 2018
quotequote all
Penelope Stopit said:
If you are measuring the voltages at the resistor packs or injectors you must ensure that they are connected to their circuits, the circuits must be complete when you measure for voltage values.

Measuring for voltage values along open circuits like disconnected injectors, relays or resistor packs will not give you the voltages that you are looking for, there are no volt drops across resistors that don't have current flowing through them

In summary - Resistors only drop the voltages in complete circuits as they need current flowing through them to do this
Very good point indeed that I hadn't picked up on. Thanks.

jensencars

Original Poster:

66 posts

72 months

Wednesday 14th March 2018
quotequote all
Hi,
thanks for that info I'm learning every day!!
so if I connect up the ECU, resistor pack and plug back on injectors should the voltage at injector plug then read 3 volt,
hi all,
I also have a relay mounted near AFM and the spring turret can anyone tell me the correct model of this relay (can only find info on carburettor overrun model) I have a standard one in there ie: live/neutral to switch soleniod and pin 30 then connects to pin 87. I'm unsure what this does but I am thinking it supplies coil negative to ECU.

mrzigazaga

18,534 posts

164 months

Wednesday 14th March 2018
quotequote all
Hi mate

Here is a very useful site...it contains the values of resistance etc to components and how to test the circuit from ECU to component.....


Hope it helps


Ziga smile
https://www.google.co.uk/url?sa=t&rct=j&q=...

Penelope Stopit

11,209 posts

108 months

Wednesday 14th March 2018
quotequote all
No unfortunately the test is not that simple, to measure for 3 Volts at the injectors supply cables you would need to have the ECU disconnected, the injection relay energised and then earth each of the injector signal cables at the ECU Pins one at a time while measuring

This could very easily end in tears if you are not careful, it will be much safer for you to measure for resistance values to begin with
With your multimeter Ohms scale set correctly and the ECU disconnected you could measure for resistance values from the resistor packs supply cables to the injector signal cables at the ECU plug - I think you have mentioned having done this but something about meter Scale Settings

You will be able to carry out a voltage values test if you are careful
With the ECU disconnected
1) Remove injector relay and bridge out the contacts so that the supply is to the resistor packs
2) @ the back of the injector plugs where the wires enter - Connect meter set @ DC Volts to the supply cable and then earth that injectors signal cable at the ECU plug - Now do the same again at the next injector and so on and so on and so on until you have checked all 8 injector supplies

In carrying out a voltage test you will have checked the injectors circuits all the way through from injector relay to the ECU plug with the injectors drawing current, this is the best test but be careful

The problem with resistance tests are that they don't give true information, many circuits check ok during resistance tests but fall over when under load, voltages measured from along live/activated circuits don't tell lies - you get what you're getting

Edited by Penelope Stopit on Wednesday 14th March 10:15

SEvans

1,159 posts

266 months

Wednesday 14th March 2018
quotequote all
One other thought when reading through this... If the injectors are open or not shutting off you could have an over fuel issue. Once the plugs are wet then maybe they won't fire. I would disconnect the fuel supply, put in a new set of plugs and spray in some Easy Start and see if it runs. Cheers Steve

jensencars

Original Poster:

66 posts

72 months

Wednesday 14th March 2018
quotequote all
Right .. thankyou very much for your assistance..
have carried out your test recommendation and found as follows:
injector:

1- 0.1 volt but can be heard clicking
2 - 3.38 volt
3- 3.45 volt
4- 3.-56 volt
5 -3.6 volt
6- 3.44 volt
7 -3.4 volt
8 -0.3 volt but can be heard clicking

also smelt a bit of fuel whilst testing, people say if I operate the throttle swiftly I will hear the injectors click unfortunately I don't..
just a thought wondering if there is an internal fault in the distributor although the resistance check match up and it has a new module on..

found in the workshop manual they have some pin number errors!!
any ideas were to go from here

jensencars

Original Poster:

66 posts

72 months

Wednesday 14th March 2018
quotequote all
SEvans said:
One other thought when reading through this... If the injectors are open or not shutting off you could have an over fuel issue. Once the plugs are wet then maybe they won't fire. I would disconnect the fuel supply, put in a new set of plugs and spray in some Easy Start and see if it runs. Cheers Steve
Thanks stuck in the office at present will get some when I get out tomorrow

Penelope Stopit

11,209 posts

108 months

Wednesday 14th March 2018
quotequote all
If you are using the same as the below diagram, double check injector supplies 1 & 8, the chances are you already have
You need to trace the loss of voltage to those 2 injectors if the diagram and readings you are getting are correct
Here is something else worth testing in case the injector signal wires are shorting together somewhere -

ECU, injector plugs and injector resistor packs disconnected

Ignition keys removed

Meter set to Ohms lowest range

In turn, measure from injector 1 signal wire @ ECU Plug to Injector 2,3,4,5,6,7and 8 signal wires - Reading should be zero Ohms

In turn, measure from injector 2 signal wire @ ECU Plug to Injector 1,3,4,5,6,7and 8 signal wires - Reading should be zero Ohms

In turn, measure from injector 3 signal wire @ ECU Plug to Injector 1,2,4,5,6,7and 8 signal wires - Reading should be zero Ohms

In turn, measure from injector 4 signal wire @ ECU Plug to Injector 1,2,3,5,6,7and 8 signal wires - Reading should be zero Ohms

And so on and so on and so on until you have verified that no injector signal wires are shorting together anywhere
Yes I know you will be duplicating some of the checks between signal wires but it's easy for me to type it this way and there is nothing wrong with double checking

You can do the same again but this time testing the injector supply wires from the disconnected resistor pack plugs to the injector plugs
You can also make sure that there is no Ohms reading from any injector signal wires at the ECU Plug to the supply wires at the injector plugs and resistor packs
Yes I know the supply wires at the injectors are the same as the supply wires at the resistor packs, the thing is a broken or broken shorting out wire can change everything and you now need to be sure

In Summary - Because you know what you are doing you need to make sure that the diagram matches your engine as there is something wrong at injector Plugs 1 & 8, due to having everything disconnected it is best that you check every wire for continuity and no internal shorts as the tests will not take long to carry out and may possibly save you cursing later after much more work only to find a short or break or.....in the injector harness

The clicking that you are getting although the voltages are incorrect does point to a wiring fault or incorrect diagram but.......??????
You will know more later

Toltec

7,159 posts

222 months

Wednesday 14th March 2018
quotequote all
I can see you have checked that you have checked that cylinder one is timed up correctly on the dizzy, are you sure the rest of the leads are in the correct order?

jensencars

Original Poster:

66 posts

72 months

Wednesday 14th March 2018
quotequote all
thanks again,
right went through everything you put on last reply no shorts between wiring etc found faults on 1 and 8 now reading 3.6volts and 3.56 volts
so am I right in thinking that the injection system is working ok? when cranking car wants to go can smell smoke from exhaust, firing but not picking up, I'm certain engine timing is ok (ie number 1 is firing on no1 compression stroke) within a few degrees need it to run to set spot on, so guessing now need to check ECU, I believe the wire from coil neg goes via a relay and triggers the ECU this checked out on continuity test cant see any resistors or anything in that line, still not 100 per cent about distributor even though I have put a new module on it and I'm getting a spark would the pick up be firing in the wrong position ? have set air gap etc. also starter motor is now getting very fed up,, eaze start!

I know this car ran very sweetly before I got it the guy took it off the road and started to restore it then I took it over