SRi 20seh gearbox problem

[Robsey]

If the eml stays on for 4 seconds or more, then the ECU should have stored any codes.

I am sure you know how to do the paperclip test.

I am assuming that a cable has not been connected or tied back properly and / or they have damaged a cable when doing the gearbox swap.
But from memory, I cannot think of any sensors that would have been disturbed simply by dropping the box.

Possibly consider an earth lead or even the gearbox to body earth strap.
Poor earths can throw up a whole array of fault codes.

[Joner1983]

I'll try a paperclip test just to be sure. The eml only seems to flash up for a couple of seconds at a time so may not have stored a code but worth a look.

A loose earth or other lead could be a good shout as it doesn't seem to affect the drive but it's constantly flashing up. I'll have a rummage around. I need to have a look at wiring anyway as the temperature gauge has also stopped working since it's been there so I've got a suspicion the cable on the sender has come loose.

[Robsey]

Hmm - how odd - that is on the thermostat housing - you couldn't get much further from the gearbox and stay on the engine.

It is just a simple female spade connector, so it could have corroded or snapped off.
Shiney plug at the end of the black sleeve.



If it happened when the box was swapped, then check the big black barrel connector by the battery. (X5 plug).

Centre of picture.

[iangsi]

As the gear box has been changed I'd start with the earth strap & see if it's been put back properly.

[Joner1983]

Thanks for pointing that out Robsey, I thought the sender was there but wasn't 100% sure so the pic helped. Turns out the wire had just come off so I've popped that back on and the gauge is working again

[Robsey]

Cool - the gauge was an easy one -
Now for the intermittent eml.

As stated - earth straps!!

Otherwise, you definitely need to do the paperclip test.

[Joner1983]

Has anyone ever produced a guide of where to find all the earth connections on each engine? I feel like this could be extremely useful to alot of people if someone has the knowledge to do it

[Robsey]

There is a thread somewhere.
But it doesn't go into much detail.

See here.
viewtopic.php?f=15&t=3506

most earth tags are in roughly the same places.

Slight differences between the main set-ups.
1 - carbs
2 - single point injections
3 - multi point injections
4 - diesels.
5 - V6 models.

From memory - look at my C18NZ image with 5 points indicated.

On the C20NE, there are additional brown earth wires on the distributor end of the metal injector rail.
Near the idle control valve and fuel pressure regulator.

[Joner1983]

Awesome, that was a huge help.

I located most of the earths including the bell housing and they all seem intact. I've done a paperclip test and it's thrown up:
65 - Idle CO potentiometer - voltage low
I'm going to look silly here but what is that??

[Robsey]

This is a quirk of Vauxhall Opel.
Looking into the diagnostics data, the CO potentiometer is identified as the throttle position valve potentiometer on the side of the throttle body.

But - when looking at fault code 65, it is said that the problem is due to the air flow meter being set wrong.
On the 20SEH and early 20NE engines, there is a plastic cap covering a mixture adjuster screw.

Ordinarily you would need to adjust this with a screwdriver.
Clockwise increases the CO content.
Anti-clockwise reduces the CO content.

But - lets take a step back. Before adjusting anything.

If the code did not exist before the gearbox swap, look at the connector for the throttle valve position switch and the connector for the air-flow meter.

Follow the wiring to ensure that everything has been connected securely.
Sometimes cables can be damaged by clumsy vehicle technicians who use the incorrect technique to unplug loom connectors.

[cavalier1990]

When I swapped out my autobox on my c18nz for a manual box I dropped the engine far too much than I should have and bust (Stretched) a few of the earths connected onto the back of the rocker cover. I think this caused me similar issues.

[Robsey]

Just had a look at my old photos.

The CO / Throttle position sensor is at the rear of the throttle body.

Looking from the front of the car.
Look to where the throttle cable is attatched to the front of the cylindrical casting.
Look directly behind the cylinder -
attached to the back of it you will find an oddly shaped black device.. only about 10mm thick with a connector at the bottom.
That is it.

See if it is connected, and that the connector pins are clean, dry and securely fitted - and there are no snapped or damaged wires.

You could check for a leaky breather, fuel or vacuum pipe in that area whilst you are at it.

[Joner1983]

Well I've had a look and everything looks normal but now the thing doesn't start. Swapped fuel pump relay with one I had lying around and check FI fuse but still no joy.

Anyone want to buy an SRi moneypit

[Robsey]

Back to basics...

Is the barrel connector connected (X5) by the battery.?
There is a black wire from here to the coil.
It gives the ignition live supply to the ECU.

Do you have an immobiliser?

Then it is the usual checks for a spark, and for fuel delivery.

It is infuriatingly frustrating when the car refuses to start.
It will be something crazy - it usually is.

[Joner1983]

Cheers Robsey, I'll have another look tomorrow. Apologies for all the posts, I'm sure everyone's getting bored of me by now but I'm pulling my hair out with this motor

[Robsey]

That is what we are here for - to help each other out.

We have all been there at one time or another.
Very few have got to the point of giving up and selling up.

If you have the use of another car, step away from the Cav for a couple of days. And clear you head.

Then come back to it with a fresh mind and eyes.

[vexorg]

Check all the battery feeds and earths if they were disturbed.

[Robsey]

Basic check list.

First and foremost - a good fully charged battery.
---------------------
Ignition Side -

Weakest item and hardest to check is the crank angle sensor. - it either works or it doesn't.

It is thought that f the engine ecu does not see enough rpm, then the pump / injector relay will not trigger.

Check that the connectors are clean dry and securely connected - back of cylinder head - timing belt end.

Check the sensor itself is okay.
Unscrew from block behind power steering pulley mount.
Take out, clean and refit. - sometimes the cheaper plastic ones can get mis-shaped when the fixture bolt is too tight.
If the body is an odd shape - replace with a metal bosch sensor.

Also check it's cable that runs around the lower half of the rear timing belt cover.
--------------------
Ignition coil-
Check for the black wire from the X5 connector by the battery to the coil.
This is your ignition live 12 volt feed to the ignition system.

Check for spark from crown lead of coil.
Perhaps you could put a spark plug in at the distributor and - put tip of plug on cylinder head and check for a spark.

Then do the usual checks to see that the distributor, rotor arm are all clean dry and in good condition.

Repeat test for other HT leads with the spark plug touching the cylinder head method as described for the crown lead.
---------------------
Fuel -

Fuel Pump -
Assuming you have a working relay...

And fuse 11 is intact. - replace with a known good fuse anyway. If the pump / ignition relay is working, it will allow 12v to pass through fuse 11.

Do you have an alarm / immobiliser?
If so - refer to alarm installer's paperwork.

Have you tried cranking the engine (coil unplugged), and tested for fuel from the feed pipes

I am tempted to say - try putting a temporary wire between battery plus and fuse 11 to bypass the relay.
The pump should now kick into life.

If not - consider a duff pump.

AND
The one that got me recently, blocked, broken or leaking fuel hose due to age. Too early to blame it on E10 fuel.
A fuel leak will give an "invisble" non-starr issue.
Especially if the leak is under the rear of the car, near the tank, pump and filter.
------------------------

General
Beyond that, we are looking at general checks for all the power feeds - red wires in the ecu loom in the driver's foot well.

And of course the full array of brown earth wires.

There is a whole array of these from the ecu that set the configuration of the ecu.

Most of these are across the back of the cylinder head or fuel rail.

[Joner1983]

It's had lots of new parts to get it back on the road including
- fuel pump
- plugs and leads
- distributor
- battery

The immobiliser has been removed last year

The cable from the crank sensor looks a bit suspect....I'll try and add an image below

I've tried spraying cold start into the air intake and it didn't even burn it off. Would this suggest I have no spark?

[Joner1983]

[Robsey]

If that is your crank angle sensor cable, then that is more than likely your culpret.

If that is duff, you will get no spark and no fuel.
No fuel, because the fuel pump relay won't be triggered to run the pump and injectors.
No regular rpm signal.

No spark because without a crank angle, the ecu will not know when to fire up the plugs.

Remember - only the Bosch part has a metal body.
When fitted, it should be routed around the lower half of the rear timing cover - clipped into the moulded plastic hooks type things.

[Joner1983]

This cable was connected ok but just loosely dangling. It may have been rubbing on the belt at the bottom. It's a very cheap and nasty arrangement at best.

I've found Bosch 0261210030 - is this the best one for the job?

[Robsey]

Here you go...







The cable is very thick and reassuringly stiff.
Like a good quality HT lead.

[Joner1983]

Awesome, just ordered one

[Joner1983]

So new Bosch senson fitted and....still doesn't start. I give up