wastegate actuator rod

[jello]

I have a wastegate problem, I think. My car was off the road for about 5 years. I'm bringing it back to life.

I'm only getting about 0.25 bar of boost maximum. I think it's a wastegate and/or actuator rod problem. My car vin ends in 38093. The wastegate actuator is threaded.

I think I could shorten the rod, and improve my boost, but that is proving difficult to get to.

Unfortunately, right now, I don't have compressed air to check the actuation.

Any suggestions?

Phil Bates

[Fredjohn]

The turbo does not operate until the engine reaches a certain temperature and does not operate when revving stationary.
Are you testing whilst actually driving it on the road?

Sorry if this is a grandmother sucking eggs reply!

[jello]

Yes, I was driving when I achieved 0.25 bar or so boost, and no more. And the car was warm.

Hell of a job getting to the actuator rod, I'll tell you what. I believe it won't be too bad if I can remove the oxygen sensor, which I have ordered a tool to remove.

I read up in my elan shop manual. Apparently I can test appropriate rod length and wastegate opening with a simple pump that will produce and measure up to about 20 psi. I used to have one of those, but I broke it. Now I will have to figure that out. I'm sure it can be done, and/or i can find/buy a pressure gauge that goes to 25 or 30 psi (about 1 3/4 bar to 2 bar).

Also, for anyone else reading these messages, I see that some versions (probably not US/California) had an oxygen sensor plug, and don't say that the oxygen sensor has to be removed to remove the heat shield and get to the wastegate rod.

Phil Bates

P.S. I have a Garret turbo kit that I gpt from LGM and others on the list. I had to make a wastegate bracket and actuator for that. Kind of difficult, as were the heat shield, coolant and oil line adaptions - but it's all available to me - it's just an even tighter and more difficult job to install and/or remove. That's why I went back to the IHI unit.

P.P.S. Until the O2 sensor removal tool arrives, on to my other issue of getting the side marker lights to light up. Probably a fuse. It's been a while since I actively worked on and drove the car - hopefully it will be on the road again soon - I put over 130,000 miles on it, and it had about 30,000 on it when I bought it.

[Rambo]

Just use Phil's simple, cheap, tried and trusted bike pump method

viewtopic.php?f=31&t=25846&p=367662&hilit=Wastegate#p327471

[jello]

Thank you FredJohn and Rambo. I should be able to diagnose tomorrow.

[lotusflasherman]

I'm struggling to understand the logic of adjusting the actuator rod length to fix a problem that has occurred.

First - I'm sure the rod length hasn't changed while it's been standing.
Second- later SE's had a fixed length rod with no adjustment possible. (See photo)

rod.jpg

Boost control is achieved by the ECU 'talking to' the Boost Control Frequency Valve. having received information* about engine temperature from Coolant Temperature Sender, boost pressure via the Manifold Absolute Pressure Sensor and throttle opening from the Throttle Position Sensor. I'd first check the wastegate isn't seized in a partly open position, check the wastegate diaphragm and then I'd be checking the electrical signals from those sensors and the state of related vacuum/pressure hoses.

P.S. * I forgot 'engine revs' too ..

[Rambo]

Good advice from Phil I'd also wondered why you were trying to change the actuator rod length as I'd never heard anyone else do this.

As Phil says, it is more likely to be stuck, bearing in mind the length of time it has been inactive. A stuck wastegate is quite a common problem if a car has been laid up for a long time and never driven

http://wikilec.com/view/Wastegate:_Releasing

[GeoffSmith]

Boost control is a closed loop system and the length of the rod is largely irrelevant (within certain limits) and is much more likely to be a stuck open wastegate.