Can anyone find out whats wrong with my car.. Reward for winner

[Frustrated Pilot]

Right,

I have an injector thats not firing. No. 1 in fact. I have checked 12v feed to the injector, have checked the continuiety on the negative. All are ok. I will be testing the amps this afternoon.

I have changed HT leads, plugs, ECU, Fuel rail, injectors and checked all are working correctly.

Now, the question is - why is the injector not firing??

Since I became redundant in Jan and have no money for a repair, and no car to get to work to earn money I can only offer a small gift to the winner of the conundrum.

Thanks all

[Dale_V]

can you list EXACTLY what you have replaced and not just checked, cheers

if you have replaced the injector, then surely it can only be ECU/wiring related. more likely wiring

[misterT]

You can try unplug each injector and check the resistance from the plug terminals, should be 2-4 ohms.

This will eliminate the injector wiring if ok.

What about the fuel pump resistor pack? (little silver box in the engine bay, by the bootlid, passenger side, the one with the square plug)

There's either 2 or 3 pins inside the connector, 2 at the top maybe a 3rd below. You can measure the resistance between the 2 terminals that are on the same side of the plug, should be around 0.73 ohms.

A couple of easy checks for you.

[Frustrated Pilot]

I hate this computer.. ive just spent tha last 30- mins typing whats been done and its crashed and lost the freaking lot!!!


Right – try again

Everything has been checked and changed apart from the ballast sensors. It is not likely the ballast sensors as it is an individual injector signal that is failing to fire. Ballast sensor failure means that no injectors would fire… not just one.

It has 12v feed and continuity on the negative.. I checked this and ran engine with a sound gun. There is no signal to the injector.

Any more thoughts?

[-:[KM]:-]

Everything has been checked and changed apart from the ballast sensors. It is not likely the ballast sensors as it is an individual injector signal that is failing to fire. Ballast sensor failure means that no injectors would fire… not just one.

Ballast resistors... not sensors. And you'll only see ~5v from them to the injectors. That's their job.

[Frustrated Pilot]

ok ballast resistors....

run me through the checks for this before i disconnect my unichip.....



then we can certinaly tell these are working



have you got a photo of the 2 wires i need to check?

the 2 boxes with the fins appear to be corroded....

sorry to seem p1sed off... but you can understand my frustration after 2.5 years of waiting ive only driven the car for 5 days before its gone wrong again and after spending £££'s i appear to be getting less than satisfactory assistance from the builder....


anyway, the ballast resistors.. they dont send the signal to the injectors to tell it to fire.. the ECU does.. but we have ruled this one out.


I will see what i can do to check the resistors.. but you will have to write a detailed check list as im not so good with multi meters

[-:[KM]:-]

To be honest, I thought it was the other way around. I thought the ECU was the switched earth. So the feed goes from battery, fuse, ignition resistors injectors, ecu then earth.

So if you have 12v pre-resistor and no 5v after, the ballast packs must be dead.

Fingers crossed for you...

[Frustrated Pilot]

i really dont know which way round it is, so you must be right.

i have 12v on one of the wires... the coloured one with a stripe..

and now i have just realised that i may have checked continuety on the coloured wire with a stripe...

in the morning i will check all the colours going along this cable to the injector.

Although i did find 3 earth wires unplugged in the engine bay.... but it has not remedied the problem.


How can I check the ballast resistors?.... talk me through it so to speak...

[-:[KM]:-]

This may help...

http://www.imoc.co.uk/forums/viewtopic. ... t=resistor


Just make sure you are checking the resistor with 5 wires. The black/red is the 12v and the others feed the injectors.

[Frustrated Pilot]

ok.. cool, I will do that ASAP then report back.. much better than ripping the unichip off... (hope it isnt that thats up the bucket)

[Frustrated Pilot]

ok, I understand what to do.....

but I dont understand how to do it...

Im not electrically minded... I have a draper multimeter with all the switches etc etc, but dont know how to use it.. (no instructions)

Which setting do i put it on..? Do I need the ignition on? battery plugged in?

[Frustrated Pilot]

just a quick update. – have to be quick TV starts soon….

Since I had never used a multimeter before I decided to call Paul Woods as he seemed a decent chap and I had loads of pm’s insisting that I give him a call.

Well, after some detective work, creating wires, looms, bypassing unichips etc he found out that the ballast resistor was not producing the correct voltage on injector 1. A quick noid light created, later revealed the ECU was indeed firing a signal and he suggested posting me a ballast sensor to cure the fault.

Paul Woods – Top Chap!! Spent over an hour on the phone with me teaching me how to use the multi meter and teaching me how to diagnose the faults, create tools for the job, and sent me parts to test.

Incidentally, a quick call to the Uni Chip people revealed a way to override the chip – basically I unplugged the unichip and bridged connections, blue to purple and white to black on the main loom and started the engine.

So if you all need to check whether a unichip works or not that’s how to test..

Mine is staying off until car is run in I think….

But hopefully the ballast resistor solves the problem.

[-:[KM]:-]

What do I win? OJ...!


Glad you got it sorted... And well done Mr Woods!