94 Escort Wagon, poor to no throttle response

[ScorpioRabbit]

Hello everyone. Thanks for reading my post.

My 94 escort 1.9l automatic wagon is having a tricky issue. Here are the symptoms:
1. the throttle does not resond
2. the exhaust heats up quickly (running lean)
3. no check engine light
4. pushing the trottle to the floor cuses the exhaust to glow red and the engine runs less rough.

Trouble shooting so far:
1. TPS has a nice steady resistance curve
2. IAC clean and moving
3. MAF checked and cleaned
4. Vacuum system thoroughly checked, twice.
5. fuel pressure solenoid(at end of fuel rail) replaced. I've even isolated it to make sure it gets enough vacuum.
6. compression good
7. fuel pressure at rail 30 psi
8. temp sensor replaced, sender tested.
9. new fuel filter.
10. Tripped and reset fuel cutoff.

I am ready to say it is the ECU, but this is an ODB1(no self checks), so I either have to buy used or put out the cash for a new one. Before I do all this I want to hear from you all if you have gone through all of this before and what you found. Thank you very much.

[Intuit]

Sounds as though you may have an exhaust restriction. Any bananas or toys in the tailpipe ? Has it been crushed to a to a slit-opening ? Note any part of the pipe that has been crushed or damaged. Also check for a distorted muffler casing. A vacuum test, would confirm an exhaust restriction. May also confirm by disconnecting the exhaust inlet pipe, (simply two bolts just after the exhaust header,) and taking it for a spin around the block. At worst, the catalytic converter is restricting flow. But this has still been pretty rare with 'scorts at this point.

[Scrapper]

Originally Posted by Intuit

Sounds as though you may have an exhaust restriction. Any bananas or toys in the tailpipe ? Has it been crushed to a to a slit-opening ? Note any part of the pipe that has been crushed or damaged. Also check for a distorted muffler casing. A vacuum test, would confirm an exhaust restriction. May also confirm by disconnecting the exhaust inlet pipe, (simply two bolts just after the exhaust header,) and taking it for a spin around the block. At worst, the catalytic converter is restricting flow. But this has still been pretty rare with 'scorts at this point.

your catalitic coverter is pluged you need to get that repaired asap it could catch your car on fire.

good luck.......

[AzTumbleweed]

I third the motion.

[ScorpioRabbit]

Good exhaust pressure, great vacuum. I've had a plugged converter before, and still had a throttle.

[Intuit]

Originally Posted by ScorpioRabbit

Good exhaust pressure, great vacuum. I've had a plugged converter before, and still had a throttle.

You may have other problems going on. But the key here is that your exhaust was turning red.

If it were "plugged," truly, you would've been loosing a ton of power on your exhaust stroke as it works to force air out. This "plugged" catalytic converter that you mentioned, probably wasn't plugged. At best it was relatively lightly restricting.

Keep in mind that there are varying degrees of restriction. The current issue sounds like a severe restriction. The prior issue you've mentioned, sounds mild; or perhaps that works the other way around.

Also keep in mind that there can be more than one issue. The only other thing that may cause this, is poor valve timing. However the engine won't stay running cold when more than a few teeth off, and a properly read vacuum test would identify a valve problem problem as well.

The 1.9L isn't a high-output engine. Running lean, I doubt is capable of turning an exhaust red, unless there were something else going on. But I could be very wrong on that.

Only other things I can suggest is to take the valve cover off and make sure that your exhaust side hydraulic roller lifters are operating properly; and to take the exhaust manifold off to check for the unusual possibility that the gasket has dropped and is obstructing flow.

(EDIT: See you already did this It is also advisable, that you check over the cooling system. (ECT, fan operation, coolant flow) A hot 1.9L will perform poorly. Check over the intake system as well.

[ScorpioRabbit]

Hmm, I'll have to drop the converter and see. The exhaust gasket is good and I already pulled the valve cover to check for bad valves and make sure the cam vs crank was positioned right according to the timing marks. The cam is dead on as well. I've had plenty of exhaust issues on various cars and never seen the throttle completely dissapear, but maybe this engine is different, I'll have to see. I'll post when I can get to it.

[AzTumbleweed]

If you have a vacuum gage a clogged exhaust will also be indicated by a low vacuum reading. Since the exhaust can't get out the fresh air can't be drawn in and that leads to the low reading.

[Scrapper]

Originally Posted by ScorpioRabbit

Hmm, I'll have to drop the converter and see. The exhaust gasket is good and I already pulled the valve cover to check for bad valves and make sure the cam vs crank was positioned right according to the timing marks. The cam is dead on as well. I've had plenty of exhaust issues on various cars and never seen the throttle completely dissapear, but maybe this engine is different, I'll have to see. I'll post when I can get to it.

i'm still saying cat is pluged or smashed to get red hot on cat.........

[Intuit]

Originally Posted by AzTumbleweed

If you have a vacuum gage a clogged exhaust will also be indicated by a low vacuum reading. Since the exhaust can't get out the fresh air can't be drawn in and that leads to the low reading.

In cases, vacuum may appear to be good but simply be slow to recover after revving the engine.