Astron running lean

[A112H]

Okay so the efi Astron is up and running, been giving me grief for about two weeks now.
So got it running and all was well in the shed, took it down the road and all good. Took it for a little run (30ks maybe) and started to miss and temp up to 3/4.
Got home and did a full check over and found a wiring issue that was "the" problem. I had both power wires to the ecu as "on" not "on" and "start". Solved that and it was better but not cured.
Back in the shed it went and I pulled the plugs which were white, so running very lean

Started looking at possible causes and decided to pull out the TN/P injectors and chuck in the TR/S injectors I had. The rational was the TN/P injectors did look a little suspect to begin with.
This made no difference at all.
I wasn't running a O2 sensor as was told it didn't need one. I had a bung in the tool box for a sensor so went out and bought a sensor, fitted and made no difference at all.
Next was fuel pressure. I had installed a Bosch 910, these run about 100psi. I thought the Magna system ran about 70-80psi. Further investigation says the Magna runs closer to 35-40psi so maybe the 910 had ruined the regulator or was just so strong it was forcing it open. If there was a free flow of fuel it wouldn't build pressure so run lean.
Well that was my idea anyway, another $200 later and I have a GOSS GE034 fitted, running 44psi and making no difference at all.
Last hope was the fuel pressure regulator. Had a good spare so swapped it over and guess what, made no difference at all.

As I am sure most of you can understand, to say I am a little bit annoyed and totally over it is an understatement

Has anyone of you had this issue? How did you solve it?

Thanks in advance

[lance]

Just reading your complaint .
You said all good in the garage and for the short run down the street.
Then you took it for the 30k drive .You thought you traced part of the problem to the extra positive wire to the computer.
Do you think that the computer may be damaged now in some way because of the wiring problem ?

[A112H]

Not sure what it is Lance, seems heat related somewhat.
Today I tried 3 different ecu's and all had the same issue.
Tried a different AFM and it helped for a while but the miss came back. Tonight I have replaced the plugs with a higher temp plug hoping to stop the miss fire when hot and I have re installed my second thermo I left of this time hoping to prevent it becoming hot to start with, lol.
So far it has all new or good used;
EFI Fuel pump
Lift pump
O2 Sensor
Spark plugs
Ignition leads
Different ecu's and fuel pump relays
AFM
Plenum
Injectors
Fuel pressure reg
Complete new and tested loom

There really isn't anything else except running a colder thermostat.

Really starting to do my head in

[shuggy]

did you prime the engine with coolant? hot spot?

do you think you could have a bad head gasket?

are you positve you are overheating and not just a higher voltage temp guage?

[A112H]

Pretty sure it is the correct sender. Sits on the first notch (1/3? on a Galant) most of the time but once it starts fucking up it shoots to the second mark (2/3? on a Galant).
It does smell slightly warm but it has never come close to over heating or boiling.
Really has got me stumped. I will grab a new sender today on the way home from work and see if it helps.
Anyone know the Triden part number for a GC/D temp sender?

[Billsy]

do you know its actually lean? as in used a wideband on it to confirm?
i wouldnt go chasing maybe problems without knowing whats what.

but first off check you dont have any intake manifold air leaks or vac lines disconnected as they will make it run lean and are easy to find.
and second id try another Air flow meter.

[A112H]

Just going by the plugs Billsy, they are totally white, not a hint of grey or brown at all

[ddt]

You may be running a bit lean but i don't think that would be causing your engine to miss when hot.
I'd be looking at the coil/distributor side of things.

[dwlee]

Have you checked the timing?

[A112H]

Cheers DDT, coil is next on the list and I do have a spare dizzy to try.

Timing is spot on dwlee, I think I have checked it like 80 times, lol

[lance]

Coil and distributor sounds good . Fuel line OK , all clean and flow nice ?

[A112H]

Yeah, fuel line is all new. Filter from tank to lift pump and filter to efi pump. All new speed flow fittings and no fuel leaks

[A112H]

Brand new coil and Galant temp sender fitted today, didn't change a thing.
Going to swap the dizzy over later with a spare and once again, fingers crossed.

I did notice one thing weird, the loom for the fuel pump sender and the sender itself are getting warm. Not hot by any means but considerably warmer (maybe 20c) than the ecu and loom next to it.
Could this be causing fuel issues?
Any ideas on why/how this could happen?

Effectively it is a Magna engine, everything is stock except the intake plenum has been flipped to suit RWD.

[lance]

Would it be a good idea to just run a temp 12 v line to the pumps to see if it makes a difference ?
How do you know that you have good fuel pressure ?

[A112H]

Yep, I was thinking the exact same thing. Might be getting too much voltage. The ecu takes its power from the Galant loom where the coil would normally get power but the fuel pump relay is getting power from a auxiliary fuse box, that is being fed from the power feed to the alternator so could be getting 14v or more I guess? Everything else from that fuse box has a relay so that would make 12v out the other side but the fuel pump relay is direct feed.
Might try a different 12v power source and see what happens.

Fuel pressure should be fine, I have two brand new pumps installed.

[lance]

l was thinking a little different. Maybe there is a problem with the wires going down to the pumps and there not getting the amps down the wires. That may make the wires warm and the pumps not to preform to good , hence the missing.
Just another idea , good luck

[shuggy]

i still think vacuum leak

[A112H]

Could be Shuggs, it has really got me fucked.
All gaskets and hoses are new so shouldn't be a leak, stranger things have happened and I am running out of other options, lol. Gotta sort it soon or it is going in the bin.

My electrical helper monkey will be here again on Sunday, if I haven't sorted it by then, his plan is to;
Relay the brown/yellow power wire.
Relay and up the gauge of the fuel pump wires.
Check all voltage coming and going all over the bloody car.

If this doesn't work, there is always insurance

[jvflash]

Hi Jason, looking at the original complaint "Took it for a little run (30ks maybe) and started to miss and temp up to 3/4" these symptoms also describe the ignition being too far advanced.
I assume this has been double checked?

[A112H]

Timing set dead on 13 BTDC, exactly as the book suggests. I have tried everything between 5 and 20 BTDC. I too initially thought timing but have been through it many times.
I am going to try a different dizzy now, if that doesn't work I am totally out of options.

[ddt]

I am going to try a different dizzy now, if that doesn't work I am totally out of options.

When it starts to misfire, does it do it only under acceleration or at all RPM?
Dunno the history of your alternator or if you had any coolant leak into it while changing over to EFI but I'm thinking your alternator could also be causing you grief as it warms up?

[A112H]

Wow, never thought of the alt ddt. It is an early Magna alt but not sure if it is carb or efi (or if that makes a difference) If it is the alt it could cause heat in the fuel pump loom and that could cause the missfire.
Once it starts missing it does it all the time, at all rev. It doesn't go away even when the engine temp comes back down.
The issue seems to be rpm controlled not speed and so is the alt. You could be onto something

[ddt]

Once it starts missing it does it all the time, at all rev. It doesn't go away even when the engine temp comes back down.

yep, in that case it's not likely to be anything fuel or air related -sounds like your alternator is putting out too few volts as it heats up (bad regulator)?
when I fitted the wrong coil to my sigma, it was putting out too few volts and was missing at all rpm -very similar symptoms.

[A112H]

Cheers mate. After spending maybe $600 on shit I didn't need, hopefully a new alternator will cure my woes.
I guess the positive is that once fixed EVERYTHING will be new so shouldn't need a spanner laid on it for 10 years, lol

[lance]

Hoping for that its a bad regulator . An easy fix and would explain you fuel wire problem and most of all your miss.
Good luck

[A112H]

New reg from the autoparts shop down the road, $60. Fingers crossed it works

[A112H]

All sorted

Fixed so many bloody things today not really sure what was the problem in the end, maybe a combination fixed it??

Sorted today;
Relays for the fuel pumps
Relay for main feed to ecu
New regulator for the alt
Thermostat removed

All is running really well now

[ddt]

Sweet!