Transmission (?) issues when cold

[xzirri]

Thank you for your reply! Yeah, I moved on to thinking the issue is related to the engine a while ago.

1. I don't have Techstream, I have just used a bluetooth OBD2 scanner with an app so far. No stored codes. I have some logs from when the engine was cold and from when the engine was hot, although I can't say that I understand much of it yet. Fuel trims seems to be approximately -10 % at their worst, although when cold, STFT never goes above 0, only negative numbers. As far as I can see, there is no data for fuel pressure in that app. I can't comment on air temperature, as I don't know what numbers are normal (starts at 42 degrees celsius, drops down to approximately ambient temperature when driving. Didn't seem too odd, as it was really hot and sunny that day). Coolant temperatures were also normal, starting at 45 degrees and steadily climbing up to 81 degrees, at which point I switched off the engine, since I no longer could reproduce the issue.

2. I have to get ahold of some equipment to do compression testing. I doubt that the dealer did a compression test when they were trying to figure out the issue.

3. Could you give me pointers on how I should check the VVTi system?

4. I am not going to follow the instructions on the spray can. I'm going to try the method used in this video. Valves before cleaning can be seen at 11:10, after can be seen at 23:20 and 35:13. If that doesn't work and I need walnut blasting, I'll just have to let it be. Blasting is way too expensive for a car this old.

[xzirri]

Just wondering, is this how I make sure the swirl flaps stay open? I'm thinking they might be the reason behind that noise, and the way it hangs on 2000 rpm before suddenly taking off makes me wonder if there is a way to test if the flaps could be the culprit or not without disassembling the manifold to begin with.

I've heard about the diesel engines having issues with swirl flaps but I can't find much info about it on this engine.

[mrfixer]

On 6/17/2020 at 7:25 PM, xzirri said:

 

3. Could you give me pointers on how I should check the VVTi system?

Check the resistance of the VVT solenoid. It should be 7-8 Ohms.  Apply Battery voltage to the solenoid terminals and it should operate.  Ideally remove it and watch it moving. There is a fine filter in there that can be cleaned.

[mrfixer]

On 6/18/2020 at 6:02 PM, xzirri said:

Just wondering, is this how I make sure the swirl flaps stay open? I'm thinking they might be the reason behind that noise, and the way it hangs on 2000 rpm before suddenly taking off makes me wonder if there is a way to test if the flaps could be the culprit or not without disassembling the manifold to begin with.

I've heard about the diesel engines having issues with swirl flaps but I can't find much info about it on this engine.

Yes, that is the switching valve for the swirl actuator.  Check resistance is 33-39 Ohms.

With Battery voltage applied the valve will open and there should be passage of air between the two vacuum ports.  With no voltage applied then air will not pass between the ports.

With vacuum applied to the swirl valve actuator (on inlet manifold) you should see/feel the operating rod being pulled.

Start engine and put in 'P'.  Operate the throttle. Solenoid should open and close according to engine speed and throttle position as below..

[xzirri]

Thanks! I'll probably test it some time next week 😊

[xzirri]

I have taken off the fuel pump, the throttle body, vacuum lines, the 5 bolts and 2 nuts for the intake manifold but I can't seem to get it off. It's like if there's not enough room for it to be pulled out. The intake air control valve assembly is even more restricted in movement, especially on the air box side. Anyone have any tips? Any screws or wiring I don't know about that I need to take off the manifold first?

Service manual states that the studs need to be removed before removing the manifold, is skipping this step really what's preventing me from taking off the manifold?

[xzirri]

For future reference, the studs have to come off. Torx sockets, E8. The vacuum thing on the intake air control valve assembly gets stuck on the intake manifold insulator, and there isn't enough clearance for both the intake manifold and the intake air control valves to come off at the same time. Hence, the studs need to be removed. There are also some electrical connectors (for the intake air control valves and the injectors, I believe) between the engine and the manifold.

I am now cleaning the intake air control valve, I'll come back with a report once I'm done.

[xzirri]

Finally done cleaning the intake air control valves. I assembled everything (or so I thought) and the issue was present even more than before. I couldn't understand why cleaning it would cause it to run worse. Turns out I had forgotten to plug in the connector for the switching valve. And FINALLY! after two whole years of not being able to pinpoint what the cause is, my engine is running fine, even when cold! The most ironic thing about it is that the swirl flaps were mentioned quite early in the process but then disregarded.

The terrible noise I was hearing was coming from the air filter box, tube or resonator, which I was finally able to locate because the sound finally presented itself when revving in neutral due to me forgetting to connect the power to the switching valve.

Thank you to everyone who have helped me on this journey! On to the next time consuming project, I guess!