Hello again. More issues with this car, swapped back in the 5 speed gearbox and got the car moving, took it for a drive this morning and getting misfire on cylinder 4. Tried swapping the plugs and coil pack still problem with cylinder 4. I suspect the wiring loom is damaged, just waiting to get my multi function tester back from a colleague to do a more thorough investigation. My question however is it possible to remove the engine loom without removal of the engine?
It could be an injector. Have you tried swapping a couple of those around?
Getting the loom off is a big job, and very fiddly under the imlet manifold.
Quote from: J.P. on March 6, 2025, 13:22My question however is it possible to remove the engine loom without removal of the engine?
Yes kind of but is a fiddly job ive done it on my old 2 twice when swapping a harness wired for Link Ecu, undo it at the ecu end and push the connectors and grommet through the bulkhead then systematically unplug and release the places where it clips onto brackets etc.
Main problem is the wiring that goes to crank sensor and knock sensor which goes down the back from aux belt end of engine, the connections onto both those sensors are very tricky to get to with engine in car! When i changed my harness i cut these wires at the cam cover and rejoined them as it was much easier, of course being critical sensors it needs to be done correctly and shield the joins etc.
Worth testing the sections you suspect before pulling complete harness off.
Thank you both, I'll check the injectors, cars been driving good for a few hundred miles now first thought was damaged harness as the car is stiff and roads are poor. Will check the injectors tomorrow or maybe this evening if I get a chance.
If you check the Fuel trims with OBD it might give you a pointer.
Quote from: Gaz mr-s on March 6, 2025, 18:03If you check the Fuel trims with OBD it might give you a pointer.
I dont have an obd capable of viewing live data.
I had some new injectors I purchased last year, fit them this morning and one of the injectors on the fuel rail wouldnt seat correctly, I ended up breaking the bolt holding the rail to the head.
Quote from: J.P. on March 7, 2025, 12:10I dont have an obd capable of viewing live data.
I had some new injectors I purchased last year, fit them this morning and one of the injectors on the fuel rail wouldnt seat correctly, I ended up breaking the bolt holding the rail to the head.
I've never touched injectors before. I have a slight disparity in my fuel trims which is probably an injector needing cleaned, - which is why I made my suggestion.
An ELM237 Bluetooth interface is under £5 on ebay, & the Torque Pro app is very cheap, used to be only Android, but can be had for Apple too.
Quote from: Gaz mr-s on March 7, 2025, 12:32I've never touched injectors before. I have a slight disparity in my fuel trims which is probably an injector needing cleaned, - which is why I made my suggestion.
An ELM237 Bluetooth interface is under £5 on ebay, & the Torque Pro app is very cheap, used to be only Android, but can be had for Apple too.
No, no, I appreciate any input. Unfortunately the broken bolt is a real problem now due to the angle so extraction will require me to drop the engine again to try and get access. I'm going to sleep on it but at this moment in time I'm completely done with this car.
Quote from: J.P. on March 7, 2025, 12:10I had some new injectors I purchased last year, fit them this morning and one of the injectors on the fuel rail wouldnt seat correctly, I ended up breaking the bolt holding the rail to the head.
I had an injector not want to go into the fuel rail recently and it was solved by using a new o-ring.
A liile smear of oil on the O rings makes it all go together smoothly.
Breaking a high quality M8 bolt takes some torque!
Quote from: Carolyn on March 7, 2025, 15:49A liile smear of oil on the O rings makes it all go together smoothly.
Breaking a high quality M8 bolt takes some torque!
I know! Total rookie move! Felt no real resistance nor did it feel like it was going "weak" just before the break. Injector wasn't sealing as o-ring had slipped and had been pinched in the rail. I thought the fuel rail bolt just needed another quarter turn but unfortunately the quarter turn was one too much.
Ill try unbolt the engine mount and get some tilt/space on it to get access. I'll get onto Toyota to get a new bolt as well in case I can manage to get it with the tools I have.
It just feels like the car just wants to be left retired at this stage. So many hours and probably close to 9 thousand euros spent at this stage its starting to get to me. I knew I would never recoup the money put in but I've yet to have any period of reliability, when it works it feels amazing but at some point I'm going to have to call it though. Its becoming good money after bad at this stage.
Quote from: J.P. on March 7, 2025, 17:41I know! Total rookie move! Felt no real resistance nor did it feel like it was going "weak" just before the break. Injector wasn't sealing as o-ring had slipped and had been pinched in the rail. I thought the fuel rail bolt just needed another quarter turn but unfortunately the quarter turn was one too much.
Ill try unbolt the engine mount and get some tilt/space on it to get access. I'll get onto Toyota to get a new bolt as well in case I can manage to get it with the tools I have.
It just feels like the car just wants to be left retired at this stage. So many hours and probably close to 9 thousand euros spent at this stage its starting to get to me. I knew I would never recoup the money put in but I've yet to have any period of reliability, when it works it feels amazing but at some point I'm going to have to call it though. Its becoming good money after bad at this stage.
Measure the length of the bolt and I'll send you one. I have loads of Toyota bolts I've stashed from engines I've stripped over the years. (PM your address). Don't give up, not yet... ;D I probably have an O ring or two as well.
Waited 72hours before making a decision then spent the last few weeks in my free time messing around with this car. Got the bolt out, found something similar in the bolts bin. Got a lend of an obd 2 scanner most misfires on cylinder 4, swapped no.3 injector for no.4 and misfire followed the injector.
I had bought 4 blue injectors last year, apparently genuine denso, they give misfire on all cylinders and fuel trims all over the place. Had original injectors cleaned and tested, one injector has too impedance and another not far behind. Toyota want 323 euro + vat per injector so that's a no from me ;D
Things ive done over the past few weeks
mixed and matched injectors
swapped coil packs with another car thats driven daily and drive great - no real change to either car
swapped maf from same car - no real change from either car
02 sensors are running fine, voltages behave as they should
checked compressions, all good
timing is good
no leaks, exhaust or intake
checked fuel pressure and its low at just over 2 bar
Also noticed very high pressure in the fuel tank? Would this be the charcoal canister failing?
So 2 injectors dead or dying and fuel pump or fuel pressure regulator dead or dying is my prognosis, what else can I even check at this point?
You can get some good used green densos from J-spec, I should think. They shuold be green ones on a standard 1ZZ.
There are lot of bogus injectors online.
Think I've got some spare stock original injectors if you want some more for cost of postage, came out ok a working engine I bought to replace my smoker.
Let me know will check if I still have them.
How did you measure fuel tank pressure? And when did you last open the filler cap? Technically they're vented caps but I know the one that's been sat in my garage for a long time builds up pressure just sitting there.
The regulator is in the pump assembly so easiest to change the whole assembly if anything. A new filter wouldn't hurt if you're already pulling the pump out.
Quote from: thetyrant on March 19, 2025, 19:51Think I've got some spare stock original injectors if you want some more for cost of postage, came out ok a working engine I bought to replace my smoker.
Let me know will check if I still have them.
If you could take a look id very much appreciate it! Would give me some more options for getting it running right.
Quote from: Call the midlife! on March 19, 2025, 20:39How did you measure fuel tank pressure? And when did you last open the filler cap? Technically they're vented caps but I know the one that's been sat in my garage for a long time builds up pressure just sitting there.
The regulator is in the pump assembly so easiest to change the whole assembly if anything. A new filter wouldn't hurt if you're already pulling the pump out.
I didn't take any direct measurement however the cap had been opened the day previously, and when I removed the feed line on the fuel tank to check out the fuel pump, a massive geyser of petrol came out, the tank should be close to atmospheric pressure shouldn't it? Very large pressure released when line was disconnected. Also had some issues a few weeks ago when filling, pump kept thinking the tank was full. It was maybe a 1/4 full.
Quote from: J.P. on March 19, 2025, 16:59Waited 72hours before making a decision then spent the last few weeks in my free time messing around with this car. Got the bolt out, found something similar in the bolts bin. Got a lend of an obd 2 scanner most misfires on cylinder 4, swapped no.3 injector for no.4 and misfire followed the injector.
I had bought 4 blue injectors last year, apparently genuine denso, they give misfire on all cylinders and fuel trims all over the place. Had original injectors cleaned and tested, one injector has too impedance and another not far behind. Toyota want 323 euro + vat per injector so that's a no from me ;D
Things ive done over the past few weeks
mixed and matched injectors
swapped coil packs with another car thats driven daily and drive great - no real change to either car
swapped maf from same car - no real change from either car
02 sensors are running fine, voltages behave as they should
checked compressions, all good
timing is good
no leaks, exhaust or intake
checked fuel pressure and its low at just over 2 bar
Also noticed very high pressure in the fuel tank? Would this be the charcoal canister failing?
So 2 injectors dead or dying and fuel pump or fuel pressure regulator dead or dying is my prognosis, what else can I even check at this point?
It might sound daft, but if the car has had gearbox swaps and other things is it possible that the loom has been disturbed at some point?
Recently had to chase a fault on my daily, seemed to be timing related and caused much scratching of heads. In the end, part of the loom hadn't been clipped on at the factory and had been fretting against the starter motor for years (totally out of sight). Eventually wore through the wrap and cable insulation to expose bare copper on the wire going to the cam sensor.
Weird situation, easily fixed, but manifested as something else.
Quote from: J.P. on March 19, 2025, 22:40If you could take a look id very much appreciate it! Would give me some more options for getting it running right.
I will take a look, ive found the coils i took off just need to remember where the injectors are, sure ive still got them somewhere!
Quote from: McMr2 on March 20, 2025, 09:58It might sound daft, but if the car has had gearbox swaps and other things is it possible that the loom has been disturbed at some point?
Recently had to chase a fault on my daily, seemed to be timing related and caused much scratching of heads. In the end, part of the loom hadn't been clipped on at the factory and had been fretting against the starter motor for years (totally out of sight). Eventually wore through the wrap and cable insulation to expose bare copper on the wire going to the cam sensor.
Weird situation, easily fixed, but manifested as something else.
Everything seems to work fine besides the dead injector, spurious injectors didnt solve the issue hopefully some oem items will do the job.
Quote from: thetyrant on March 20, 2025, 10:11I will take a look, ive found the coils i took off just need to remember where the injectors are, sure ive still got them somewhere!
No worries at all happy to exchange some beer tokens for them if they do turn up, havent found much stock locally as of yet.
Picked up some injectors and fuel trims are back where they should be, engine still sounds like its missing though took for a short drive and its still stumbling and bogging under load. Took it home and plugged in the obd scanner and there was a pending p0420, sensors are new so I guess that only leaves the cat. I'll try remove the 02 sensors and see if it changes its running today if I get time.