88 Turbo Coupe. New problems, no power

A couple of years ago, I bought an 88 Turbo Coupe automatic with only 42000 miles. I haven't driven it much because I have other vehicles. However, whenever I did, everything worked as it should and it drove great. It now has 44000 miles.

Recently, out of nowhere, my turbo boost fell to 5 lbs max. However, the car still ran fine in every other regard. I assumed the waste gate was stuck open. Before I got around to checking on the waste gate, another issue popped up. One day I fired it up and it was running a little rough and had VERY lazy throttle response. I decided to take it around the block anyway. It was literally like it had 10 horsepower even though the engine was running mostly smooth. Just NO power.

Strangely, the check engine light never came on. I assumed it was the TPS by the way it was acting. Apparently those are unobtanium OEM or aftermarket now, so I had my Ford dealer do a nationwide search and I bought the last three they could find.

I bought the idle stabilization plate / device at the same time because occasionally, my idle would ramp up to 1500. I installed the idle plate following all the instructions and the new TPS at the same time. I've done it before on my other Bird which has 425,000 miles. I didn't get around to setting the TPS yet, but just put it in the middle of its range where they generally run.

I started the car and immediately had very high idle {2500) and a check engine light. The only way I could get the idle down somewhat was by cranking the TPS all the way to one end of its range.

I did that and took it out for a short drive anyway just to see if power seemed normal. It did within the limits of my still 5 lbs max boost. I stopped at a local store for a minute and when I came out, it ran rough again and was back to feeling like 10 horsepower. Barely made it home.

So clearly, the TPS was not my original problem for the rough running, lazy throttle and no power.

Because of other more pressing concerns in life and work, I took it to a local mechanic with Ford dealer experience. When I drove there, it ran fine, except for still only having 5 lbs of boost.

They reset a couple of things, got the idle down and pulled code 22 and 23. We believe 23 is because the thermostat was stuck open and the car was taking waaaay too long to get to running temp. If that's true, a new thermostat should take care of that.

Code 22 pops up again every time within seconds of clearing it. The mechanic is getting conflicting information when he looks it up online.

Some info says it's the ABS, another says it's the MAP sensor, another says it's the TPS.

At this point, he's waiting on me to provide him with some direction.

Unfortunately, the mechanic has limited experience with cars of this age and was just starting his career near the end of ODB1. His older retired Ford mechanic buddies were of no help.

Since some of this started and the check engine light came on when I installed the idle plate and TPS, I'm thinking he should pull them and reinstall them himself following the instructions.

I followed the instructions on the idle plate installation and it's articulated the same direction as my other Bird has been for twenty years.

However, I don't know what would happen if it were installed backwards, meaning flipped back to front.

Any thoughts on any of this?????

Thanks for reading my "War and Peace" like post. Somehow, I'm unable to communicate anything in a few sentences.

Thanks
Damon

Code 22 is for the BARO sensor. The 2.3T does NOT use a MAP sensor. The MAP and BARO sensors look identical. There should NOT be a vacuum hose running from running from the BARO to intake vacuum.

Code 23 is TPS voltage too high. HAve you checked TPS voltage between the black and green wires at the TPS?

FYI, the PCM has NOTHING to do with the ABS system, and ABS codes are stored in the ABS computer in the trunk.

It sounds to me like you have a HUGE vacuum / boost pressure leak. Check ALL vacuum and pressure lines for splits, disconnected, etc. Pay special attention to the turbo to IC and IC to throttle body tubes.

For future reference some engine codes are different for different car lines or models. This certainly is for TC. For future reference see http://www.tbirdheritage.com/turbocoupe/...-Chart.php

Let us know what you find on the current problem.

Also, almost no mechanic know much, if anything, about these cars and that's been true for a long time.

My guess would have been a vacuum leak also but who knows. I have seen & heard some odd things with these birds.

I was actually curious about the cat... I assume all 87-88 birds had recalls as mine did. Not sure why they were recalled but maybe yours are clogged? just a thought. And also with such low mileage... was there signs of mice damage anywhere in the vehicle?

It sounds like the OP's problem came on suddenly, and a clogged cat happens over time. But, along those lines...... Years ago, a friend took his 84 Fiero out of winter storage (i.e., hadnt run on months) and it had zero power, ran like crap, but had run perfectly before he put it away. A bunch of troubleshooting turned up a HUGE mouse nest in the back of the cat converter plugging the exhaust. Dropped exhaust, cleaned it out, and it ran perfect again.

I been thinking along the same lines but for the air filter box and the intake tract back to the turbo.

This might be unrelated but I had a mystery intermittent drive-ability issue that I think was the BARO sensor. The car would randomly stumble and drive like crap. After this happening 2 or 3 times I noticed on my wideband gauge that for some reason the engine would run super rich when it was having an episode.

I had replaced nearly every sensor at that point except the BARO. I can't confirm this was the issue because instead of buying the part I installed the PIMP I had on the shelf for 2 years. The problem did go away after that though.

I agree with the tests listed by everyone else. You can cross a lot of things off the possibilities list with a $20 digital multi-meter.

I'm not sure if I missed this but did you use a multi-meter to adjust the TPS? The TPS calculates 'load' on the engine and adjusts the ignition timing accordingly. If it's off and you are not getting enough timing advance, I think that can cause what you're experiencing.

I have found pressurizing the intake is the best way to find vacuum or boost leaks. It's fairly simple to make a tool with a couple of hardware store parts.

Just a few ideas. If you find all the obvious possibilities are good (vacuum/boost leak, VAM is good, TPS, etc.) you might consider testing the BARO :beer:

Still have the Boost Control Solenoid connected? Do you get more boost in Premium fuel mode? Sounds like you may have a missing ground/signal return issue.

John