Engine won't rev and hunts

[Laird Scooby]

What a bummer! Stupid question - you did wire it up correctly? This is the correct way :



Got that from Airtex to confirm before i fitted mine.

It crossed my mind if the old one was wired the wrong way you'd have followed that and perhaps carried the fault on. That outlet hose should get pretty hard if it's working correctly.

I take it you've fitted a new fuel filter and also checked there isn't water in the fuel tank? If there is water in the tank, there's an easy fix, add some meths to the tank. It forms an emulsion with the water then mixes with the petrol and that way, the water gets burned off. Usually causes misfiring/bad starting though.

The other thing, what's the history of the car? Did you drive it before you bought it, did the fault appear suddenly and so on? I've got a few ideas about other things to check but wondering if there are any clues to be had in the history..

[ANDTWENTY]

Originally Posted by Laird Scooby

What a bummer! Stupid question - you did wire it up correctly? This is the correct way :



Got that from Airtex to confirm before i fitted mine.

It crossed my mind if the old one was wired the wrong way you'd have followed that and perhaps carried the fault on. That outlet hose should get pretty hard if it's working correctly.

I take it you've fitted a new fuel filter and also checked there isn't water in the fuel tank? If there is water in the tank, there's an easy fix, add some meths to the tank. It forms an emulsion with the water then mixes with the petrol and that way, the water gets burned off. Usually causes misfiring/bad starting though.

The other thing, what's the history of the car? Did you drive it before you bought it, did the fault appear suddenly and so on? I've got a few ideas about other things to check but wondering if there are any clues to be had in the history..

presuming that red is + then it was wired correctly at the pump, there was a small + and - in the plastic by the terminals so I went by these and at the boot connector the pink wire from car goes to the pink wire at the tank etc.

when you say filter are you meaning filter under the car or strainer on the pump? I got a new strainer which went on but I haven't done the filter under the car, although this looks fairly new from what I saw.

I couldn't see any water in the tank, looked like normal petrol, the fuel light was on when I got it and I put in another 5 litres the other day.

History wise its 1 owner from new, he had it "serviced" every year and mot'd at the main dealer with all paperwork and steps to back it up, 2 years ago he lost his leg but still had the car serviced but sadly passed away a year ago. Since the service the car has done 14 mines which is the distance from the dealership to his house and to the persons house I bought it off which happens to be a mechanic at the dealership.

As far as I know when it went for the service 2 years ago it was running fine and was driven to and from the centre, since that the chap said that the gardener of the man had started it periodically to run it, other than that I don't think its been driven. The guy I got it off had to tow it back to his but I'm not sure how long he had the car as to how long the issue has been occurring but my guess is something has stopped from being sat around, although it was kept in a stable or barn so wasn't outside.

Not sure if it is relevant but the radio doesn't work nor does the ariel. There are also a lot of lights on the dash, some half lit some fully lit, I will try add pictures and a video in a moment.

Starting to pull my hair out on this one, the plan is to have it on the road for oct 1st so I can get a whole month tax on it and get a whole months tax back on mine.

[ANDTWENTY]

Here is a video of the cars rpm gauge, at first I slowly press the accelerator, then back to idle then I pump the throttle. The idle is quite high I noticed, not sure if this is normal on these, the adjustment screw is also wound all the way in on the throttle butterfly

https://youtu.be/m96P5Vi2sJs

these are the lights incase you can't see from the video:


Here is the air filter that was replaced 14 miles ago... I think not:


The new fuel pump:


the old fuel pump:

[Laird Scooby]

Have you checked the cam timing? It's not unknown for the timing to jump if a car has been sat for some time and if it's jumped a couple of teeth, it might not be capable of running.

Worth checking the feeds to the undebody fuel pump and that it's running and definitely checking the cam timing.



That's the basic set up for the cam timing, crank pulley should be the same but changed on later models.

Yes, i mean the fuel filter under the car in the cradle - judging by that air filter they may have only wiped it clean! Also check you have a feed to the main pump while you're under there.

[ANDTWENTY]

Originally Posted by Laird Scooby

Have you checked the cam timing? It's not unknown for the timing to jump if a car has been sat for some time and if it's jumped a couple of teeth, it might not be capable of running.

Worth checking the feeds to the undebody fuel pump and that it's running and definitely checking the cam timing.



That's the basic set up for the cam timing, crank pulley should be the same but changed on later models.

Yes, i mean the fuel filter under the car in the cradle - judging by that air filter they may have only wiped it clean! Also check you have a feed to the main pump while you're under there.

I haven't checked the timing but sounds plausible! I'll have a look in the morning and also check the pump and filter, will see if I can get a new one tomorrow too. I can definitely here the pump prime when the key is put at II so would assume that it would be working.

I tried the map sensor again and it defiantly doesn't run well with it out, also tried the car with it out from starting and its not right so could this be faulty perhaps because it definitely seems like something it working.

should the idle be that high too? is that a sign of something else along with the idle air code? could that be at fault?

[Laird Scooby]

If someone has played with the throttle stop screw the idle could be too high now. However that or even an AICV fault won't cause the problem you're getting.

Have you tried dead-ending the fuel line to bring the pressure up? If you have a hydraulic hose clamp (like you use on a brake flexi hose when changing a caliper for example) fit it on the return hose from the fuel pressure regulator (FPR) and clamp it to bring the pressure up. If it then revs happily, it would point to a dodgy FPR as well.
If you don't have a hydraulic hose clamp, two smooth handled spanners with the handles crossed, one either side of the hose and then clamped with a pair of Mole grips will do the job.

There should also be a vacuum hose on the FPR, check this is intact and secure and also that the manifold stuib it goes onto is clear and not blocked.
If you pull the vac hose off the FPR with it idling and put your thumb over the end of the hose, wait and watch for fuel coming out of the stub on the FPR - shouldn't happen.

The big thing now is nobody knows when this problem started, whether it came on gradually or suddenly so we're shooting in the dark somewhat. I'd check the cam belt timing first as that's pretty likely then work through the other things, probably next would be to check the feed on the underbody pump (could be corroded terminals that just need cleaning) then the FPR to see if you can find any clues as to what's causing the problem. Might be several problems there.

[ANDTWENTY]

Originally Posted by Laird Scooby

If someone has played with the throttle stop screw the idle could be too high now. However that or even an AICV fault won't cause the problem you're getting.

Have you tried dead-ending the fuel line to bring the pressure up? If you have a hydraulic hose clamp (like you use on a brake flexi hose when changing a caliper for example) fit it on the return hose from the fuel pressure regulator (FPR) and clamp it to bring the pressure up. If it then revs happily, it would point to a dodgy FPR as well.
If you don't have a hydraulic hose clamp, two smooth handled spanners with the handles crossed, one either side of the hose and then clamped with a pair of Mole grips will do the job.

There should also be a vacuum hose on the FPR, check this is intact and secure and also that the manifold stuib it goes onto is clear and not blocked.
If you pull the vac hose off the FPR with it idling and put your thumb over the end of the hose, wait and watch for fuel coming out of the stub on the FPR - shouldn't happen.

The big thing now is nobody knows when this problem started, whether it came on gradually or suddenly so we're shooting in the dark somewhat. I'd check the cam belt timing first as that's pretty likely then work through the other things, probably next would be to check the feed on the underbody pump (could be corroded terminals that just need cleaning) then the FPR to see if you can find any clues as to what's causing the problem. Might be several problems there.

I don't have any of those pliers but i'll be able to clamp it off. thanks for the suggestions, should give me some stuff to work through! I found a filter in Norwich which I have reserved so will pick that up and chuck it on while I'm under the car. I feel like its going to turn out to be something simple, just a pain to track down!!

[mocambique-amazone]

Thank you for the vid. This explains a lot!

First: the alternator isn't charging. Check for wiring and earth. The earth is a separate wire.

And this hunting isn't fuel related!

A really simple fault. The TPS isn't opening.

Let the car idle until warm up and remove the connector. Try to open the throttle again.

Report.

Even better: check the TPS via the diagnostic box in modus "2"

The faulty idle control valve will be a faulty idle control, I won't believe, or a wrong connector on it.
Did the "I notice a maintenance on the invoice and didn't a full maintenance because of " earning money this way is easy" " workshop noticed a changed inlet manifold gasket?

To adjust a manipulated butterfly "idle control screw" proper will be much easier on the bench. Cleaning the butterfly us easier on the bench too.

I'm to tired to write more.
Stop buying and trashing parts.

Good luck, Kay

[Laird Scooby]

Originally Posted by mocambique-amazone

Thank you for the vid. This explains a lot!

First: the alternator isn't charging. Check for wiring and earth. The earth is a separate wire.

And this hunting isn't fuel related!

A really simple fault. The TPS isn't opening.

Let the car idle until warm up and remove the connector. Try to open the throttle again.

Report.

Even better: check the TPS via the diagnostic box in modus "2"

The faulty idle control valve will be a faulty idle control, I won't believe, or a wrong connector on it.
Did the "I notice a maintenance on the invoice and didn't a full maintenance because of " earning money this way is easy" " workshop noticed a changed inlet manifold gasket?

To adjust a manipulated butterfly "idle control screw" proper will be much easier on the bench. Cleaning the butterfly us easier on the bench too.

I'm to tired to write more.
Stop buying and trashing parts.

Good luck, Kay

He's definitely right that the alternator isnt charging! I missed that last night (had a seriously stressful two days, say no more!) or i would have said something. Like i said much earlier in the thread, you need to sort the charging problem first. Either the replacement alternator isn't working or you've wired it up wrong or there's another charging system fault.

[ANDTWENTY]

Originally Posted by mocambique-amazone

Thank you for the vid. This explains a lot!

First: the alternator isn't charging. Check for wiring and earth. The earth is a separate wire.

And this hunting isn't fuel related!

A really simple fault. The TPS isn't opening.

Let the car idle until warm up and remove the connector. Try to open the throttle again.

Report.

Even better: check the TPS via the diagnostic box in modus "2"

The faulty idle control valve will be a faulty idle control, I won't believe, or a wrong connector on it.
Did the "I notice a maintenance on the invoice and didn't a full maintenance because of " earning money this way is easy" " workshop noticed a changed inlet manifold gasket?

To adjust a manipulated butterfly "idle control screw" proper will be much easier on the bench. Cleaning the butterfly us easier on the bench too.

I'm to tired to write more.
Stop buying and trashing parts.

Good luck, Kay

the alternator is giving 14V to the battery when the car starts so would assume that the alternator is working, it was a second hand one off a diesel so perhaps the thin red spade connector I put in the wrong spade on the alternator?

I have tested the throttle position sensor by back probing it and it was fine and also did the diagnostics yesterday, it flashed to say it worked. I then tried it in mode 6 I think where you can test full open and fully closed, I kept getting 3-3-3 for fully open but not 3-3-2 for when it was closed or idle it just flashed 3-3-3 too