Freshly rebuild 4AGZE now running great with added clutch problems!

[worldwalker]

So I've finally got phildo's 4AGZE that he rebuilt up and running. As mentioned in another thread, the wiring wasn't suited to my car so has been returned to factory using the original sensors. It has new plugs leads cap and rotor (still same old coil and igniter). The rebuild looks good, everything in the right spot to the right torque and in the right direction; but something's wrong. It runs like shit and has a loud top end knock.

It took me about 5 hits to get the fuel through and the engine to fire but it died instantly. A few jiggles here and there and plugged in the temp sensor and it runs.
It hesitates on gentle revs to 2000.
It struggles to idle smooth.
It hunts but over a long period, 20-30 seconds not just up and down and from 800-1500rpm
And it has a god awful top end knock.

Oil pressure is good, it fires first time now it's been run, it smooths out slightly once the revs are stable above 1500. I havnt added coolant and its exhaust ends at the cat. I don't have a timing light but have checked the cans crank pistons and dizzy are all in alignment.

Does anyone have an idea where to look next? Both to get it smooth and shut it up?

Engine fixed itself with a kick in the guts... Now its the clutch...

Update Edit:

I've run it on stands for 10km bringing the revs up to 3-4000 in 4th then holding the clutch brakes and accelerator until the clutch slips but still wont release.

I wasn't even able to get it into gear stationary, so I bit the bullet, jump started it and drove it around at about 50km/h. It didn't grind any gears but with the clutch in and racing the engine the clutch slipped easily and the car wouldn't accelerate further but the plate still wont release enough to engage the gears stationary.

Is there anything else I can do before pulling the engine out again?

Thanks,

Nick.

[TERRA Operative]

Top end, I'd be checking cam clearances and making sure everything is tight.

[worldwalker]

Yeah that was my next move, but have run out of time for now. The other thing I forgot to mention was that the engine has sat for 4ish years rebuilt with only a film of oil. It was all free however, and its first compression test came in at 167/165/167/163.

Thanks,
Nick

[bk_]

OEM ECU? OEM injectors? OEM FPR?

spark plugs OK?

how is fuel pump connected? What fuel are you using? Fuel stored in the shed for 6+ months? or fresh from the petrol station?

Rewired eh? ground 100% OK? Is the engine mounted in a vehicle (doesn't sound like it if there's no coolant?)

I dont remember phildo's setup as he had like 3 or 4 4AG engines in the shed

[worldwalker]

All factory, all new except for coil/igniter (all new filters, fluids etc). Injectors rebuilt and cleaned, Larger SC pulley and high comp HG. The wiring is factory strait off an auto and appropriate changes for neutral start switch, reverse lights etc using auto ECU; A few of the sensors are off of the auto 4AGZE that was in the car, all were working fine and engine ran ok with no codes thrown (no codes with the current engine either but only run short periods). Fuel tank drained and 10L of fresh ultimate 2 days old in there. Engine's in the car, just run out of time filling fluids, so thought I'd crank it over and run it for a couple of mins (engine/exhaust warm to touch then off).

This is the 4AGZE that was going into his NA ADM 87 AW11.

[bk_]

high comp headgasket? so is the compression ratio different to OEM?

Got a wideband controller setup that you can chuck on the exhaust? That would help massively in diagnosing the issue, whether AFRs is within expected range (12-13 AFR when cold, or low 14s when hot)

[worldwalker]

Comp is 167/163/165/163psi and factory is 156 and a min of 121. No idea what the change to ratio is but small I'd say. I don't have a wideband controller unfortunately but from what I understand they run rich enough to handle mild changes without too much consequence.

[Hatta1978]

Hi,
The hunting at 800-1500 sounds familiar for a leak in the manifold system maybe. Or the throttle position sensor is faulty probably. Maybe you should get a timing light handy.
Can you explain about the top end knock a bit?
Regards.

[worldwalker]

Hi, thanks, I'll get onto the timing light asap and see how it goes, my feeling is its spot on but might not be a clean fire from the coil. I've currently got jumper leads running from the negative terminal to the block to ensure a good earth too.

I'll try swapping the TPS with a spare and check for leaks but I've checked the torque on the bolts and they're all ok and I've replaced all the vacuum lines.

The knocking is insidious of an exhaust cam out of timing, that typical "miss" knock. Its about as loud as the clicking you get from a loose exhaust gasket, but sounds like the soft valve tapping/clicking you would normally expect from an DOHC. I'm thinking it is either a stiff valve spring from sitting for so long or the cams are loose, either way it looks like the covers are coming off .

[Cuzzo]

There is a few essential ingredients missing by the sounds of it. First if its an unknown engine you really should be checking clearances to all things that have been modified or even pulled apart.

Coolant is needed to stop the thing hunting. Vaccum leaks wouldn't help either. If it afm? If so I'd be also ensuring its getting clean air and afm is not damaged.

After all that check timing. ensuring your locking the timing to 10degrees. However you will only be able to time it correctly once up to operating temp....again needing coolant.

[Hatta1978]

Hi,
I agree with cuzzo on the vacum leaks, manifold bolts tigtness does not fully insure the vacum seal. Gasket and o rings also can cause most vacum leaks.
The way you discribe the knock is maybe it actualy is a "knock" or "a ping". Maybe you are familiar with it. Its a term used to indicate the piston vibrating during reving. it mostly occure during acceleration or wide open throttle under load when the air fuel ratio is not correct. Lean burn to be exact. The air intke is higher than the fuel supplied. With a supercharger, i think it can damage your engine if not monitored properly.
I forget, does the 4AGZE use a MAP sensor or MAF sensor?
Regards.

[Phildo]

Nick!! Great to hear she's lost her ignition-ginity, sorry to hear it doesnt run as smooth as it looks (yet).
Wonder if ADZ is still trolling these forums, he'd be excited to know it's finally firing up and always seemed keen to offer thoughts about obscure issues.

Please keep us posted + Merry Christmas!
-Phil

[worldwalker]

Hi Hatta, the knocking/rattling is coming from the top end, it doesn't sound like pinging. The noise is continuous and the car is still on stands so no load on the engine yet. This GZE has a AFM gate, the later models had a MAP, the airflow meter is in good condition and working as it should but I will retest it and possibly swap it for a spare. Whole intake tract has been resealed with new gaskets, and would I be right in saying form-a-gasket too Phil?

Where I've removed parts to suit my car everything has been 100% as per the workshop manual, all the torque settings are correct, correct replacement of single use parts etc, I can't imagine where the intake would be leaking from, though I'll double check all the areas, anywhere in particular that they're prone to leak would help, as its a tight squeeze. I'm more inclined to believe its my own stupidity (and laziness) not taking the time to bleed the coolant before I started it as I know this has caused hunting for my cars in the past.

We'll get there Phil! Baby step, every time I take another look I get a step closer. I'm still happy with the way its going and wasn't expecting an engine thats been sitting for a few years to run perfect first go anyway. Main thing is, its all in sealed up and it runs, just need to track down these 2 issues and it'll be time to take it for a test drive! You'll be happy to know we've also stripped the blue top and red top and in the process of rebuilding them now, so the white AW11 will live again! Oh and of course, with all the spares I did manage to get my crap box aw11 up and running too. It's handy having a shed full of spares.

[Duk]

The 4AGZE (certainly the AFM version) are quite sensitive to TPS setting.
A dead TPS will cause some shitty low load driving behavior that will show up as lean transition AFRs. A dud TPS will show up in a diagnostic check.
You will need to follow the workshop manual on how to set them up (even a Gregory's manual for the Aussie Corolla has the correct setup for the 4 pin TPS and it works on the 4AGZE).

[TERRA Operative]