1.2 12v AZQ - Down on power

[hutchysrs50]

Basically...

The timing chain failed and jumped two teeth.

While replacing it I changed the valve guides and valves.

Compression is now spot on at 210, but it doesn't drive well at all.

Max speed is 40mph on flat ground and 20mph on a slight hill. Doesn't Rev past 4,000rpm in any gear, but in neutral will Rev fine. It's cut out a couple of times also.

It got a full service with new spark plugs, oil and filter and air filter.

So far I have...

Cleaned egr valve

Cleaned throttle body

Replaced map sensor (if left unplugged it drives slightly better)

Cleaned lambda sensor

Drove with exhaust manifold slightly loose.

[hutchysrs50]

Not sure if this is a good or bad thing but keep getting a fault codes...

Cylinder 2: misfire

Cylinder 3: misfire

Random/multiple cylinder misfire

This only happens if sitting on idle I Rev it and hold my foot to the floor for about 3 seconds it will hiccup and then give the above codes.

[sepulchrave]

Misfires like that are usually the coilpacks, suggest you swap number 1 and 2 and see if the misfire follows.

[hutchysrs50]

I did as you suggested previously and swapped coilpacs for piece of mind if or ever came back.

When in neutral and revved hard for a few seconds those fault codes come up but are random, I've had cyl 1,2&3 and random multiple misfire at the same time.

[Taylor93]

Thinking out loud...

 

Engine at idle revs fine (No real engine load)

 

In any gear, the engine is loaded, so would adjust ignition timing, based on Knock sensor, and Cam position sensor.

 

Sure they are plugged in properly?

 

I know the 1.4 MPI is based mainly on the cam position for advance/retard of ignition but when the sensor fails it is designed to run off of the knock sensor, basically advancing it until it detects a knock. Then retards it.

 

 

Just a suggestion as the head has been off n all that.

[hutchysrs50]

I checked it was plugged in today as the plug is right beside the crankshaft sensor as it happens.

The timing is fixed as far as adjustment goes, will all be done from the ECU.

It really has got me puzzled, I'm feeling very defeated by this fault, I really don't know what to do next, I'm guessing give it to the experts that can use a scope to check all the sensors and do some logs to see what's at fault.

Unplugging the MAP sensor is throwing me a little though, it drives better but still not right, so I'm thinking its linked somehow.

[sepulchrave]

I did as you suggested previously and swapped coilpacs for piece of mind if or ever came back.

When in neutral and revved hard for a few seconds those fault codes come up but are random, I've had cyl 1,2&3 and random multiple misfire at the same time.

 

Coil pack or injector loom faults?

 

Starting to suspect you have a duff ECU.

[hutchysrs50]

Googling it has brought up ECU a few times.

Great.

[Toxicvrs]

Googling it has brought up ECU a few times.

Great.

I've got a 1.2 6v ecu if it's of any use

[hutchysrs50]

Sorry, it isn't. 1.2 12v AZQ engine code.

[Taylor93]

Even if you changed the ecu they are coded to the immobiliser in the dials so you osuld need that coded.

Have you tried disconnecting both battery terminals and shorting them together?

My mpi had countless fault codes which would not clear and pointed at a duff ECU after the shorting of the disconnected battery leads it fixed it. Flashed the ecu so to speak.

[hutchysrs50]

I would get the ECU swapped over and coded correctly.

Yeah I've done all the usual battery reset stuff. I can do it all via diagnostic equipment anyway for all learned values etc.

Think I'll try doing some logs on Monday. I've never tried on a 1.2 so don't know what I can do, can do anything on the diesel so should be ok.

[xman]

Injectors?

Check the chain/valve timing, one tooth out and it'll be crap.

Edited 28 March, 2015 by xman

[hutchysrs50]

Could well be injectors but I don't know which one and no fault codes leading to them.

Timing is spot on, checked it a few times. I checked it yesterday when changing the crankshaft sensor, made sense to pop the timing pin and lock the engine, all 3 fell in no problem at all.

Today I have...

Put all the standard sensors back in.

Reset all values in adaptations and entering "00" to reset them all.

Adapted the ECU and throttle body with "60" and egr valve with "74" I think it was.

Left it to idle for about 15 minutes while cleaning it up, took it for a spin and it's worse than ever, cutting out far more frequently.

Monday, fuel filter and a genuine coolant temp sensor. Will check spark plugs, then it's off to the dealers.

[sepulchrave]

Fuel pump or fuel pump relay, check fuel delivery pressure to the rail and check it doesn't fall when you rev it.

[hutchysrs50]

I'm afraid I don't have a fuel pressure tester. Not something I've ever needed to invest in.

[sepulchrave]

I'm afraid I don't have a fuel pressure tester. Not something I've ever needed to invest in.

 

 Can't you borrow one for 5 minutes?

[fordfan]

What's the MAP sensor showing - readings wise?  It could be the EGR not closing correctly and messing up the manifold vacuum.  You could rule it out if you can blank it off temporarily.

[hutchysrs50]

I have blanked the egr valve off, didn't help.

As for live data, I havnt done any logs, not sure what channel it is or what to look for really.

I could try and borrow one I supppse, the trouble is getting to the garage to ask to lend it.

Thanks for the suggestions though

[hutchysrs50]

Apart from sensor and wiring faults, can anyone suggest anything internally that could be wrong?

From rebuilding the cylinder head and changing the timing chain.

Timing is spot on and compression is spot on, does this rule out the internals really?

[sepulchrave]

Apart from sensor and wiring faults, can anyone suggest anything internally that could be wrong?

From rebuilding the cylinder head and changing the timing chain.

Timing is spot on and compression is spot on, does this rule out the internals really?

 

Yes, completely.

[hutchysrs50]

Thank you.

As well as the fuel filter and CTS I'm going to check and gap the spark plugs as well, something I just replaced and forgot about I suppose.

[hutchysrs50]

Apparently the fuel filter has a regulator so thought I might as well change it, didn't make a difference.

Coolant temp sensor was just changed because it was nice and easy and not very expensive, didn't susspect this as the gauge reads fine and fine on live data.

Anyway, changed them both, no difference, booked in the garage for Wednesday.

Watch this space....

[hutchysrs50]

A few things I've thought about.

The flywheel, although solid isn't the best, I'm thinking once it's up and spinning at a higher speed it might be loosing the pickup from the crankshaft sensor.

Other thing being if the bottom end isn't located properly on its key way, but that's just over thinking it because I can't actually see or check it. Timings spot on so should be fine.

[Taylor93]

But none of those things were changed were they?

 

 

You have removed the cylinder head, and since then there appear to be a misfire.

 

If it is timed correctly to the timing marks, its unlikely the bottom end has gone out of time. 

 

You removed the head, so provided good compression, it has to be:

 

Coil Packs/Spark Plugs

Injectors/ Fuel Pressure

MAP Sensor

Cam Position Sensor

Knock Sensor (although unlikely as it is detecting the misfire)

With the possibility its the 02 Sensor.

 

Or a damaged Wiring loom.