Loss of power

The AFM box is a finicky beast. If there is something blocking or causing the flapper inside to not move freely, that will affect performance.

AND, there is a very small cutoff switch inside the electronic box on the AFM that is a safety shutoff for the electric fuel pump, if damaged, it could cut off the fuel pump. Don't forget to check the wires to the fuel pump. If loose, they may not be making full contact, which could cause fuel pressure issues too.
 
Well knowing this car it sat for 10 years in barn without being driven, that may have something to do with it as well.

TonyK.

Grimsby Ontario Canada.
 
Ya, I thought that too. I’ve changed the fuel filter back to the “old” one. I’ll take it for a drive tomorrow and see what’s what. Thought I’d eliminate the easy one first...
 
Well, it’s not the fuel filter....My next guess is either dirty fuel injectors or something to do with the afm. Although, all I did was remove the afm and clean it...wouldn’t think it would be that temperamental..
Perhaps when I was driving with the one fuel injector unplugged it got gummed up....
 
Check the pin connections in the electrical connection plug. I had a spider once where one of the pins had pulled back into the connector block and was not making contact into the connection on the AFM.
 
Mike how are you making out. I have a spare Mass Air Flow sensor here you can take home and try when you are here tomorrow. I also have a complete engine that has the fuel rail and injectors on it, but it will take a bit of time to remove if from the engine. The engine is sitting on the shelf in the barn. As for the comment that the cars are finiky, I will disagree. A properly running engine is almost bullet proof and can take a lot of abuse. Let one sit for 10 years and expect the same may be asking a lot, but once refreshed it will not let you down.

TonyK ( Uncle)

Grimsby Ontario Canada.
 
carl said:
Check the pin connections in the electrical connection plug. I had a spider once where one of the pins had pulled back into the connector block and was not making contact into the connection on the AFM.
Click to expand...
The dual relay has a history of pushed back pins, too; particularly the little pin 85.
 
I had it idling yesterday and it seems good. I have many theories but the most suspect is dirty gas. This car had sat for a long time so I think that a good fuel system clean over the winter is in order.
I bought some Lucas fuel treatment and am going to add it today with some 94 octane (the grade I’ve only used) and drive down to Grimsby.
I thought that It might have been the afm but again I refuse to believe that cleaning it caused any harm. I checked the pins on the harness as well and all is good. Any frustrations I’ve had for this car quickly dissipate after a nice drive down the road with the top off. :)
 
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Ok, changed the air flow meter care of Mr Tony K. Still no change. Before I go and start spending money on other things, I had removed the throttle position sensor and cleaned it before. Is there a trick to setting it? Could the bogging on acceleration and difficulty starting be a symptom of an incorrectly set tps??
 
The Throttle Position Switch on Bosch L-Jetronic is a simple device that only tells the FI control box one of these three things:
a. The throttle is closed
b. The throttle is not closed but not wide open
c. The throttle is wide open

Given this very narrow skill set, it's unlikely that the TPS is the cause of your issue, unless when you say "acceleration" you are referring to Wide Open Throttle acceleration.

But it's easy to check, simple test light stuff---see the FI troubleshooting manual for details, pages 27 and 58.
 
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I found this...
 
Ok, I set the tps and no change. Then with the ignition key set to “on” I disconnected the filter and pushed the plate on the afm in and checked to see if the fuel pump was turning on which it is. I haven’t checked the fuel pressure yet but now I’m somewhat at a loss...
Could it be a plugged or bad injector? I did drive a couple hundred kms with one disconnected....
I’ve pretty much checked everything else....

It idles ok. A bit high (reading is about 1200-1400) assuming the tach is accurate which I question) but ok. When I go to press the gas pedal it’s labouring and I feel like I have to get the revs high to drive off smoothly. Then when I want to accelerate (not even full throttle) it seems like it’s revving ok but there’s very little power and the best description I can come up with is that it sort of “bucks” like the power cuts in and out.
 
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Ok, update. I checked the fuel pressure as described in the manual and all is good. It’s right where it should be....also, and maybe not such a big deal but the PO had used 8mm hose as replacement....
 
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I have had this problem before on other cars. After exhausting all other possibilities I discovered it was an exhaust restriction, specifically a clogged converter. You might try disconnecting the exhaust and see if the power comes back.
 
Mike, you don't have to wait until winter or spend a lot of money. Just unbolt the catalytic converter and see if it's clogged. The engine power and performance will instantly return although a bit loud with open exhaust. The honeycomb structure in the converter tends to break up into chunks with age and miles. I "redesigned" both of mine that collapsed with a tire iron. Just break up the honeycomb over a trashcan until it's all out. Bolt back on. Fixed!
 
I like your style! :) The stock setup is awful. It rattles and squeaks and lends nothing to the sound.
I’ve gone ahead and ordered the stainless header and muffler combo from vicksauto. I’ll be posting a nice thread about the removal, install, fit and most likely a video of the sound.
Just another “excuse” to replace the exhaust. ;)
 
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