Engine won't rev and hunts

[ANDTWENTY]

Originally Posted by Laird Scooby

Just wanted to make sure you meant the brush and not a bush, Has caused a few problems in the past!

Plugs, i prefer NGK but most reputable makes are good - Champion is not a reputable make! Make sure you check and set the gap correctly, 0.65-0.70mm, no more, no less or you will have problems. If it had a service, the plugs should be new or at least in good condition but bearing in mind the air filter, they may be on their last legs!

If you car is 1990, it DOESN'T NEED A CAT!!!

Only cars from 1992 onwards need one and sometimes even then, they don't, depending on chassis and engine codes.

For example my other beast is 1994 and is eligible for the BET Emissions test otherwise known as the non-cat test.

If you lay under the car and hit the cat with the palm of your hand, if you hear any rattles from inside it, there's a fair chance the honeycomb structure inside has collapsed.
When i say hit, i mean just hard enough to rattle it, don't hit it like you'd hit someone as if you wanted to kill them!

just checked the dizzy, the brush is fine, nice and springy and in good condition, its an ew cap and rotor but appeared to be something on the terminals inside so cleaned that off so they're nice and clean. I'll stick the new plugs on and give it a test, I got Bosch ones, they didn't have ngk, normally use Bosch and they are good from what I can tell.

thats good news on the cat then, I just assumed that if it was fitted it was needed, will have a listen and maybe take it off to see if its okay/ runs without.

[ANDTWENTY]

Just changed the plugs, they were pretty black and filthy, the gap was also about 0.81mm so too big, put a set of new ones in and gap set to 0.66mm but still the same issue.

the cat has a bit of a rattle in it so will drop it out and see if I have a running engine.

[ANDTWENTY]

Didn't manage to get the cat out completely as the pipe from the cat to the muffle are fairly stuck together but I managed to get it out the way so the header just went out and this didn't solve the problem! although it did sound nice!

Back to the drawing board I feel

[ANDTWENTY]

Originally Posted by Rversteeg

All the air that passes through the idle air control valve has also passed the LMM, hence the correct amount of fuel should be injected, irrespective of the position of th idle air control valve. It merely controls the idling speed, no mixture enrichment.
Have you checked the MAF for loose chips of foam that could have come out of the air filter box? The foam can desintegrate and if a flake is sticking to the measuring wire inside the MAF it will stop working correctly.
No LPG installed? It could in that case be running on two fuels.

Sorry I seemed to have missed this post, been a busy day!

Yea that makes sense and I did think that may be the case but I was running out of things to blame so thought maybe I could blame that haha

I have checked the MAF sensor and it looked to be clean, I couldn't see anything on any of the wires but perhaps theres a tiny bit, I was going to clean it off but all I had was brake and clutch cleaner, thought this might not be the best so will order some maf cleaner.

There no LPG but once its running the plan is to convert it as I'll be using it as a daily and do quite a few miles to work so would like a cheaper running cost!

[stegreg]

Hows the dizzy cap and rotor arm? worn gaps, or even a crack, could loose ht spark with similar symptoms....worth a look.

[ANDTWENTY]

Originally Posted by stegreg

Hows the dizzy cap and rotor arm? worn gaps, or even a crack, could loose ht spark with similar symptoms....worth a look.

Both are brand new and having taken them off today and inspected look good, didn't see any damage and theses no misfire or bad idle which I would expect

[Laird Scooby]

Originally Posted by ANDTWENTY

Didn't manage to get the cat out completely as the pipe from the cat to the muffle are fairly stuck together but I managed to get it out the way so the header just went out and this didn't solve the problem! although it did sound nice!

Back to the drawing board I feel

It's beginning to look a lot like the MAF, can you see a part number on it? Preferably the Bosch part number.

Also you seem to have missed a question earlier - is it an estate?

[ANDTWENTY]

Originally Posted by Laird Scooby

It's beginning to look a lot like the MAF, can you see a part number on it? Preferably the Bosch part number.

Also you seem to have missed a question earlier - is it an estate?

I tend to agree, I've checked most physical items that I can think of which makes me believe it's a sensor issue, the TPS seems to get a reading but I haven't checked the MAF, any idea how to check a 5 wire mad sensor? Not keen to replace it as they look to be expensive!!

Yes it is an estate, sorry was a bit over the place yesterday.

[Laird Scooby]

Originally Posted by ANDTWENTY

I tend to agree, I've checked most physical items that I can think of which makes me believe it's a sensor issue, the TPS seems to get a reading but I haven't checked the MAF, any idea how to check a 5 wire mad sensor? Not keen to replace it as they look to be expensive!!

Yes it is an estate, sorry was a bit over the place yesterday.

If you tip the back seats forward, you can lift up the flaps to access the three nuts scuring the middle part of the floor covering.



THey are 13mm nuts, that's the drivers side 40% split on the rear seat shown, there are two nuts in the 60% side. Remove them, lift the front edge and pull forward to reveal the access plate for the in-tank pump/sender unit :



Remove the 4 10mm heaed bolts to reveal :



Yours won't have the NRV in the 12mm bore fuel line like mine had as a test, it should go straight onto the outlet stub on the in-tank pump/sender unit. Try squashing that 12mm bore hose with your fingers with the engine off. Then start the engine, let it idle and try squashing it again. If you can still squash it, the in-tank pump isn't working.

That would mean the underbody pump isn't getting the fuel it needs to be able to generate the pressure when the engine is revved.

If the pump isn't working, remove the cubby hole cover behind the left hand whel arch and locate the three-pole multiplug that has red, brown and grey going to the tank and pink, brown and grey on the car side. Use your multimeter with the engine running on dc Volts and check you have +12V on the red/pink wires with respect to the brown wires. If so and the pump isn't running, the pump is FUBAR - adding some fuel to the tank to get it above about 1/4 full may well get it going simply on the siphon effect but no guarantees.

Try checking that out before condemning the MAF, if the pump turns out to be dead, give me a shout and i'll point you in the direction of some sensibly priced ones.

[ANDTWENTY]

Originally Posted by Laird Scooby

If you tip the back seats forward, you can lift up the flaps to access the three nuts scuring the middle part of the floor covering.



THey are 13mm nuts, that's the drivers side 40% split on the rear seat shown, there are two nuts in the 60% side. Remove them, lift the front edge and pull forward to reveal the access plate for the in-tank pump/sender unit :



Remove the 4 10mm heaed bolts to reveal :



Yours won't have the NRV in the 12mm bore fuel line like mine had as a test, it should go straight onto the outlet stub on the in-tank pump/sender unit. Try squashing that 12mm bore hose with your fingers with the engine off. Then start the engine, let it idle and try squashing it again. If you can still squash it, the in-tank pump isn't working.

That would mean the underbody pump isn't getting the fuel it needs to be able to generate the pressure when the engine is revved.

If the pump isn't working, remove the cubby hole cover behind the left hand whel arch and locate the three-pole multiplug that has red, brown and grey going to the tank and pink, brown and grey on the car side. Use your multimeter with the engine running on dc Volts and check you have +12V on the red/pink wires with respect to the brown wires. If so and the pump isn't running, the pump is FUBAR - adding some fuel to the tank to get it above about 1/4 full may well get it going simply on the siphon effect but no guarantees.

Try checking that out before condemning the MAF, if the pump turns out to be dead, give me a shout and i'll point you in the direction of some sensibly priced ones.

Thank you for this!! had the car idling for about 5 mins and I have no pressure in that pipe!! think you may be on to something here!

when you say left wheel arch do you mean in the back? if so I don't have a 3 pin I have a 4 pin, the colours are pink brown grey and black and on both sides, any idea if this is right and if so which side is car and tank, mine is mounted vertically with a wire going up and forward and one comes from the right of the car and up into the connector.

addition__

Just tested the wires, with respect to the brown, the pink gives 13 volts but the grey gives only 7, is this an issue being only 7?