I already have a thread on many of my problems, but it has veered off so far from it's og problems that I thought I'd post a new one. I had water ingress into my ECU which had caused the black connector and it's respective pins to corrode. The car wouldn't start but after a new connector which I soldered on and a new ECU the car starts again. My problem now is that the engine rattles a lot when idling, it seems as if a piston isn't igniting. The ECU I got off of ebay has all the same numbers as mine so I don't think it needs to be re-coded (I have no clue if this is true so someone with knowledge of ECU's please confirm or deny). The car has been sitting for about a year so maybe that has caused some new problem? I also cleaned out the engine bay, removed some tubes and wires then put them back, but I cant find any obvious leaks that would cause this problem. Another thing I've noticed is that my coolant level had decreased to a very low level, the temperature gauge also isn't working and my coolant warning light is on. I added some water but the light is still on and gauge is still not working. I removed the sensor to see if it might just be dead but upon doing that the car runs even worse so I'm guessing it's fine. I'm hoping to get any ideas as where the problems could lie, I'm not very mechanically savvy (this is my first car) so I'm really not sure what I'm doing. Any suggestions would be appreciated!

 

Well done on getting her re-lit!
Given the back story of your car, I would now be inclined to turn my attention away from the ECU, at least for the time being. Your video clip is very short, but does seem like a regular "hard" misfire, which would suggest a stuck injector or a failed coil pack. Try disconnecting the coil packs one by one with the engine running, which should enable you to identify whether it is indeed a single cylinder misfire. If you find a coil pack which you can disconnect without affecting the engines running, that is a dodgy cylinder. Swap the coil pack with one of the good cylinders, and see if the misfire transfers. If it does, you have a failed coil pack, a common fault on these cars ( see many threads) If the misfire doesnt transfer, suspicion would fall on a stuck injector, again a common fault on cars which have been laid up, again covered in numerous threads.
Correct temperature readings are important for idle speed and economy, but would be unlikely to cause a misfire like yours. Checkout the various threads, and remember that the sensor which drives your temperature gauge is NOT the one which the ECU uses.

 

So you have a spot of stumble under the bonnet .

There have been reports of the aft most # 5 and # 6 ignition coil wires being swapped

With a new ECU there is a concern of the throttle position sensor closed throttle value matching the setting inside the ECU

There is a concern if the TPS connector is engaged and locked with the metal bar

There is a value of 0.60 + or - 0.02 volts DC on the Green / Yellow return wire ( middle wire on the connector ) to the ECU , you can nick the wire insulation as it comes over the fuel rail . The connector must stay connected for the sensor to be powered up with the 5.0 volt DC reference .

You can check this value with the engine not running but the ignition key in the on position

The term orientation is what is used and will take some time to develope a understanding and work around to resolve ( if that is the issue )

There is also the original O2 sensors being used for fuel trim ( rich / lean mixture ) after the coolant temp ( 2 wire connector ) goes up to the trigger value to go closed loop full engine regulation . This should be relearned by the new ECU after a while and is included ( and apart from a relearning process ) in the ECU orientation process

There have been reports of the O2 sensor square connectors being swapped as they are the same

Do you have 4 O2 sensors on your engine and the ECU is for a 2 sensor setup ? The US has 4

I have an early morning appointment so may not be back in until late tonight

 

Thanks for your tip! Progress has been made. I checked all the coils as well as the spark plugs, theres no issues with any of the coils. The spark plugs were okey as well but I changed them anyway to be sure. Cylinder 1, 4 and five are sparking but cylinder 2,3 and 6 are duds. I've swapped around spark plugs and coils between all of them and the theme remains. In other words, the car is running on three cylinders. I'm going to keep trouble-shooting and reading up online.

Does this sound familiar to anyone, then dont be afraid to send a tip.

 

When you say 2, 3, and 6 are duds, have you established that there is no spark, or that the cylinder isnt firing? Could there be spark but no fuel? Multiple stuck injectors after a long lay up is by no means unprecedented.....

 

Good question, I haven't checked that out. How would I go about establishing if there is a spark or not? And I've tried to find information on stuck injectors but I cant seem to find exactly what I think I'm looking for. I'm sure it's in a thread somewhere but what exactly do you do to fix a stuck injector. Do you clean it out or does it have to be changed?

Edit: I found a great video explaining how to check the injectors so I'll go do that

 

A lot of this flew right over my head but I'll try to take a look at it. I'm almost certain that my car is made for the UK market so does that mean I have 2 O2 sensors? The ECU was bought from England so i cant be sure but I think it was used in a British car as well. And what exactly does orientation mean, is it something the ECU does on it's own? I'll try to establish if the TPS has the correct value. If ignition coil 5 and 6 were swapped then shouldn't both be misfiring? In my case 5 works but not 6. Thanks for your help!

 

You have established that the coil packs are good by switching them around. To establish whether you are getting spark to the "dud" cylinders, test that you are getting an electrical input to them.
Injectors can be swapped round too, so it might be worth establishing whether your misfires migrate by doing so.

 

Does the stumble occur the second the engine is started with a cold engine coolant temp or after it warms up ?

The injectors should all have power " sitting " on them from the same source which is the large ECU controlled relay so it would be unlikely that one or a few are missing power .. But you can swap this relay with a headlight relay in case it has burnt power contacts inside limiting the current flow undermining the injectors operation . This same relay powers up about 1 / 2 of your engine sensors and is the needed and used at all times 2nd power source for the ECU .

Each individual injector is provided a ground to open the injector by 6 wires to the ECU

Each injector has a basket filter that can be removed and replaced if some are clogged other then running some injector cleaner through the moving parts of the injectors . Textron is a recommended cleaner from Chevron

Old fuel ?

Bad fuel from the last station purchased from ?

Main fuel filter changed ? 2 o - rings required

On the item of orientation of the ECU we can look at that later as there are some other quick checks :

Some one had broken a tooth on the ring gear the CKPS looks at so he had 2 missing teeth which confused the ECU

The crankshaft bolt is a 34 mm to crank it around

Clean the face of the CKPS that looks at the missing tooth as deposits can degrade the CKPS signal

The CKPS can degrade to the point of failures of the different uses of that one signal the ECU provides , These failures can occur without giving you a CEL code of P0335

Someone had good results in cleaning the EGR valve seat , The engine has a history of a bad air / oil separator for the crankcase gasses entering into the intake manifold

Editing

 

None of the three cylinders had any spark so my suspicion lies on the ECU now again. All of the wires for the coils that are connected to the black connector on the ECU have a good connection despite my novice soldering job. Im assuming that theres something going on in the box that is causing this problem.

 

Coil 2, 3 and 6 listed from back to front of the engine are all missing a spark, would any of the above mentioned problems cause this to happen? And shouldnt that rule out the injectors as the root cause?

 

Upon looking at the new ECU and it's old B connector I saw that theres been a change in the wires for the CPS. My old ECU and the connector still in the car has a red and a blue wire on PIN 23 and 26 which connect to a common ground. My new ECU had a white and orange wire instead. Maybe someone knows if this could affect anything.

 

When you mentioned that you had 3 cylinders out, my thoughts did momentarily turn to the issue of the cylinder "banks" . You will find these referred to in connection with the O2 sensors in particular, as these are dedicated one sensor to each bank of three cylinders. That said, the two banks are cylinders 123 and 456, so your numbering suggests that your problem is unrelated.
The complete absence of an input to 3 cylinders would lead me to test the continuity of your wiring from the coils to the ECU; the loom may have been damaged somewhere, or perhaps there is an anomaly at the connector.

 

Everything seems okey there as well...

I was thinking about swapping out the PROMS from the old to the new ECU. Maybe that could be some cause of my issues. I'm still unsure if the low coolant light could be related.

 

I can follow your logic back to the ECU. When you said that the replacement ECU had all the same numbers as the old one, I take it you mean the entire code was the same, ie numbers AND letters?

 

Exactly, the only numbers that were a bit off was the date code. But it was still in the same year.

I changed the PROM chips but that didnt help. Not sure what to look at next...

 

follow the wires

 

Hi Connor,

xalty may be referring to this in his cryptic way: have you tested the integrity of the wires from the ECM to the ignition coils in the dead cylinders by doing the following?

With the ECM connected and the ignition ON:
1. Confirm supply voltage is present on the White/Pink wire at each coil connector;

With the ignition OFF and the battery and ECM disconnected (in that order):
2. Test each ground wire (the Light Green wires with different tracer stripe colors) for low-resistance continuity (near 0 ohms) between the ECM connector and the coil connector;
3. Test each ground wire for a short to the power supply wire;
4. Test each ground wire for a short to chassis/engine ground
5. Test each of the ground wires for a short to any of the other ground wires;

The insulation on the coil wires is known to become brittle with age and heat, to crack, and to literally fall off the copper wires. A common place for this to happen is at the bend in the harness at the rear of the cylinder head, inside the outer wrap or covering where it is not readily visible. It is also common along the top of the cylinder head. If any of your electrical measurements above are questionable, it would be worth carefully cutting away the wrap from the harness at the rear of the head and carefully inspecting every individual wire for any damage to the insulation.

You don't mention whether there was any oil on the spark plugs you removed. The threaded sleeve of the spark plugs and the threaded ports of the cylinder head are the ground path for spark, so if oil has leaked past the spark plug tube seals down into the tubes, it can seep down the spark plug threads and add considerable resistance to the spark ground path, leading to misfires. This is a very common issue.

Just because you don't have spark doesn't mean you don't also have issues with some of the injectors. You may have to check both.

One method of testing the injectors is to remove them, and try to blow through each of them. You should not be able to blow through any injector. Now supply power to each injector. A 9 volt battery connected with alligator clips will work. With the injector powered, you should be able to blow through the injector. That is a very basic way to test the solenoid valve inside the injector.

To test for partial clogging requires a little more work, but one (messy) method is to reinstall the injectors in the fuel rail, but not into the manifold; reconnect the electrical connectors for the injectors but disconnect the ones for the coils (IMPORTANT). Place an old towel on the engine. Put safety goggles on to protect your eyes from spraying fuel. Hold the fuel rail with the injectors aiming downward about 4 inches/10 cm above the old towel. Have an assistant briefly crank the engine and watch the tips of the injectors from the side. Properly working injectors will atomize the fuel into two fine conical sprays. Clogged injectors won't spray at all. Partially-clogged injectors will squirt one or two streams or just dribble droplets of fuel. Obviously, you don't want to crank the engine too long and spray a large quantity of fuel everywhere and risk a fire.

If you find that all of your injectors are opening and closing properly but that some are partially clogged, they can probably be cleaned. I use the Techron that Parker mentioned. I use it in its concentrated form and force it through the injector under 20 psi of air pressure. Somewhere in the photo albums at the link in my signature are photos of the apparatus I made for cleaning injectors. Unfortunately the large images at Jag-Lovers are still down, but the thumbnails and descriptions are still visible.

Cheers,

Don

 

Did you have the same issue before DIY soldered wires to ECU? Your issue appeared to be damaged wires to ECU. Only if you are in the State, I have a spare connector to the ECU that you can have for free. If I recall, 1997 wire to ECU are not the same as 1995 and 1996.

 

Hi Don, thanks for that information. When I check for shorts do I check from the ECU connector with the coils connected or do I check from the connector that attaches to each individual coil? I tried it both ways: When the coils are connected (I check from the ECU connector). The grounds have resistance between each other, they also have resistance to the engine. When I disconnect the coils there is no resistance anymore.