9a help needed desperately!!! - SORTED!!!!

[pumbaa 0]

My valver is literally sucking the blood from my very veins!

 

I've fitted a p&p'd head, inlet and throttle body, a 4-branch, abf cams, dizzy, isv, injectors, k&n and rohr pipe.

 

I've managed to get the car to start and idle. But when ever I try to rev it, the revs drop and takes ages to pick up if not die altogether. If I pull the throttle very gently the revs will gradually grow and when above say, 2000 it revs fine. The problem is just coming off idle.

 

Now I've tried putting back the old isv, dizzy, air filter, and throttle body one by one but to no avail. Putting the old throttle body back seems to make some difference but the problem is still there. The car isn't really drivable and is taking up space at my dads garage.

 

I've checked for air leaks and found none. I've even done the bad thing and adjusted the mixture but still no improvement.

 

Does anyone have any suggestions or know someone near north London that might be able to help and won't rape my wallet?

 

Any help is much appreciated as I'm at my witts end!

 

Thanks,

 

Kunaal

[farrantino 0]

sound the the idle control swithc not letting go, check the connections on the TB and make sure there clean and not damaged, also make sure the micro-switch click in and out.

 

sean

[dirtytorque 0]

can only suggest checking all the basics,cam/ignition timing and fuel pressure.

I take it it was working fine befor all the mods?

[pumbaa 0]

The car was running fine before all the mods. On the old throttle body there are 2 switches, for idle and full throttle. Both click in and out. will give them a clean though anyway with fingers crossed!The ported throttle body has what seems like a potentiometer instead. Does this make any difference? The TB with the potentiometer clicks on/off idle but not full throttle. Is this normal? Have also checked and re-checked timing but not fuel pressure. Fuel supply was fine before and once i get it above 2000 revs it runs fine so i wouldnt expect it to be fuel pressure related, or am i missing something? Im thinking it might be metering head or related but i dont want to go buying a new one without making sure.

 

Thanks for your help guys,

 

Kunaal

[easypops 8]

You might want to check that the 2 small vacuum pipes are connected, the ones that go on the underside of the rubber pipe bit that connects to the throttle body........and make sure the wiring for the throttle potentiometer is sound

[pumbaa 0]

2 vacuum pipes connected, check. Gonna give the throttle body wiring a check. Only way to test i can think of is to remove it from the car and send a current down one pin and see if it returns through another, then move throttle and see if it disappears and re-appears at the other pin when at full throttle. If you get what i mean?

[easypops 8]

2 vacuum pipes connected, check. Gonna give the throttle body wiring a check. Only way to test i can think of is to remove it from the car and send a current down one pin and see if it returns through another, then move throttle and see if it disappears and re-appears at the other pin when at full throttle. If you get what i mean?

 

I'm more of a 'wiggle it about and see if there is any difference'..........this is where the bad idle was on my old valver.........2 of the 3 wires were split inside the plastic sheathings, only found it by luck/total frustration after changing fuel pump, air mass meter , throttle potentiometer, leads, coil, plugs,distributor,throttle body(with yet another potentiometer).........once i had rejoined the wires it ran perfectly for the next couple of years until i sold it.

I'd just unplug it when its running, rev it and see if there is any change?

 

Good luck mate :salute:

[davidwort 0]

I'm thinking metering head too.

Was it sat for long dry when the engine work was done? did it get dirty at all? does the plunger move smoothly when you lift the air flow plate gently?

Have you tried an injector spray pattern test (into bottles) with the airflow plate at idle and just above?

The 9A metering head should not be adjusted at all, the equivalent to the idle CO setting adjustment on the 1.8 K-jet 16v is pre-set at the factory on the 9A and would take specialist knowledge to calibrate properly again.

[pumbaa 0]

Going to try putting the original injectors back and see if there is any difference. The metering head was kept in the car boot for 3 weeks while the engine work was done. The plate moves smoothly with constant resistance when lifted. Will try a spray test after I've done a thorough check of all throttle body wires. I know i shouldn't have touched the mixture but i was getting desperate! I figured it may have needed to be tweaked since the engine will be flowing more air so i gave it a try :( Anyone have a spare metering head that hasn't been tampered with and is in guaranteed perfect working order if all else fails?

 

Cheers for all the suggestions,

 

Kunaal

[pumbaa 0]

Does anyone know exactly what i should see if i unplug the wiring going to the throttle body?

 

Kunaal

[pumbaa 0]

Right, update on my blood sucking valver!

 

Checked all pipes and hoses - no leaks

 

checked all switches and wiring - no problems

 

changed injectors back - no difference

 

checked timing - spot on

 

changed metering head for a known working one with tamper seal in place (thanks aide!!) - no change

 

unplugged the 2 wires going to the metering head so the ecu basically runs like a KR - engine doesn't die completely like before when revved but doesn't run smoothly.

 

This tells me its something to do with the feedback loop? - am i right?

 

Plugged it into a diagnostics machine - tells me there is a fault with the idle actuator - but the car idles fine, its just coming off idle.

 

so i cleared the code and re-scanned - no problems, code does not re-appear.

 

I left the car running with machine attached, revved it a bit (by first slowly pulling throttle till the revs built up above 2000) set the machine to scan again and it came up with an o2 sensor fault!

 

It has a genuine bosh lambda but i will try to replace this on monday.

 

Does anyone know if its ok to extend the wires of the lambda for this car? After putting in the 4-branch i had to extend the wires to reach a new lambda hole further down the exhaust (there is no cat btw) is this ok to do?

 

Hope the new lambda fixes the car - will let you know.

 

Thanks

[easypops 8]

What about the 5th injector?

[aide 0]

changed metering head for a known working one with tamper seal in place (thanks aide!!) - no change

 

no probs, glad it arrived ok, shame its not cured issue though.

 

it sounds to me like the control pressure in the upper chamber of the metering head is a wee bit high, this will resist upward movement of the air flow plate from idle but not when air flow increases, i don't know the 2ltr very well, but the pressure in that chamber is controlled by an actuator in the black box on the side of metering unit, would guess it gets it's signal from the potentiometer on the throttle body and the ecu, maybe that's what the throttle fault means :scratch:

[pumbaa 0]

Ok, changed the lambda.... no joy. Gonna cry.

[pumbaa 0]

Just had a thought.... has anyone ever done an exhaust cam mod on a 9a and not a kr? I'm thinking maybe the ecu cant deal with the emissions due to the overlap created. Im using a chopped abf exhaust as inlet and kr exhaust. I know its an odd combo but i know it works on a kr.

 

Thanks,

 

Kunaal

[dirtytorque 0]

Does sound odd.

well if ur at the point of despair swap the cam back and see if it solves ur prob?!

[pumbaa 0]

Yeah, im gonna have a go at that but was hoping to get the car running by sat night so i can pick the mrs up at the airport on sun morning. Don't think i'll be able to get the cams swapped over in time. :(

[aide 0]

i'd check the various fuel pressures around the metering head, i have the correct readings at home, but you'll need to buy some fuel pipe, pressure guage, T piece and means of connecting to fuel pipes.

 

everyone seems a little scared of doing this, but it let me set up my old valver properly once i'd got the kit together.

[pumbaa 0]

If you weren't in Belfast i'd pay you to come down and fix the C!

Currently feeling pretty shit about it. Thinking about throwing it the garage and leaving it forever or selling it for a massive loss and getting any old piece of crap to drive. Really am felling pretty depressed about it all.

 

Hopefully i'll better in a few days and will want to try again. :(

[farrantino 0]

Have you tried the temp sensor on the right had side of the head under the water flange, as this sensor tells the ECU the engine temp.

 

ALso could well be one of the pumps, check inside the boot and hear out for a buzz, and do the same by the bottom of the drivers door.

 

Not sure if the above has been mentioned, but i am work and cant read all the prev. messages.

 

Sean.

[pumbaa 0]

Changed the temp sensor already. Will listen for the fuel pumps tomorrow but im pretty sure theyre ok as the car ran fine before i f****d with it. Im gonna try sticking some kr or abf cams in in the morning if i get the time.

 

Anyone know how i can definately tell the cams apart without measuring them? (dont have verniers) I know the kr's have some of the back of the lobes cut away on inlet and exhaust but do the 9a's have this too? I was under the impression the 9a and kr exhausts were the same.

 

Also has anyone ever tried abf inlet with kr exhaust in a 9a?

 

Cheers guys

 

Kunaal

[farrantino 0]

just a quick thought, is the timing spot on ?

[pumbaa 0]

Yeah, ive re-marked the cut exhaust cam and rotated accordingly. The lobes line up as they should. I'm gonna pop some abf's or kr's in tomorrow morning anyway. I'm pretty sure the timing is ok because once the revs are up above about 1500 she runs fine. It just has one mother of a flat spot moving off.

[aide 0]

If you weren't in Belfast i'd pay you to come down and fix the C!

Currently feeling pretty **** about it. Thinking about throwing it the garage and leaving it forever or selling it for a massive loss and getting any old piece of crap to drive. Really am felling pretty depressed about it all.

 

Hopefully i'll better in a few days and will want to try again. :(

 

hey man i'd of popped down already if i was local :) its a pain in the ass when they don't run right .

 

kr and 9a exhausts are exactly the same lift and duration, not sure if there is any particular distinction between either type.

 

what you need is an old school mechanic who knows how to diagnose faults on mechanical injection systems, there's bound to be someone round your way!

[pumbaa 0]

Cheers aide,

 

The old man used to be a bit of a k-jet guru...... About 20 years ago! But now has moved on to more modern engines that need a computer to tell you what's wrong. Anyway, he's about as stumped as I am. He reckons it might be the cams as well so he's gonna help me stick a matched pair in tomorrow.

 

Does anyone know how tell abf's or kr's apart from 9a's? Don't really want to be sticking 9a's in.

 

Cheers