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2.9l Power Loss when warmed up


unobtainium

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Hi, this is my 1st post, and I'm having issues with my '87 BII. It'll drive fine for about 3 minutes after I start it up, but then I get a popping sound from the engine compartment, I cant go past about 3000 rpm or 35 mph, and i slow down to about 10 mph if i try to climb a hill. Any tips would be awesome. Thanks,
 

rusty ol ranger

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Hi, this is my 1st post, and I'm having issues with my '87 BII. It'll drive fine for about 3 minutes after I start it up, but then I get a popping sound from the engine compartment, I cant go past about 3000 rpm or 35 mph, and i slow down to about 10 mph if i try to climb a hill. Any tips would be awesome. Thanks,
1- pull codes

2- Do a vacuum test (this will check for a plugged cat)

3- Compression check.

Sounds like a plugged cat to me.
 

SenorNoob

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unobtainium

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I ordered an EEC 4 code scanner... It's supposed to arrive today.
1- pull codes

2- Do a vacuum test (this will check for a plugged cat)

3- Compression check.

Sounds like a plugged cat to me.
Compression's even across all cylinders.
I don't know how to do a vacuum test but i do know that the exhaust was modified by the previous owner and the cat convertor was removed - there's just 2 straight, rusty pipes with a couple glasspacks now.
 

rusty ol ranger

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I ordered an EEC 4 code scanner... It's supposed to arrive today.

Compression's even across all cylinders.
I don't know how to do a vacuum test but i do know that the exhaust was modified by the previous owner and the cat convertor was removed - there's just 2 straight, rusty pipes with a couple glasspacks now.
Alright....then cats arent the issue.

Pull the codes....if i had to guess id say coolant temp sensor or possibly a MAP issue.

It may not hurt to check fuel pressure if the codes come back empty
 

unobtainium

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Finally got the scanner... codes are 63, 54, and 95.
 

unobtainium

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I know that 63 is there because the TPS was taken off.
 

SenorNoob

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Get that back on, clear and try again. 95 is interesting. I wonder if could be indicating the fuel pump cutting out under load? IAT signal high would have PCM thinking the incoming air really cold right? When you did the compression test, what did the plugs look like?
 

unobtainium

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Get that back on, clear and try again. 95 is interesting. I wonder if could be indicating the fuel pump cutting out under load? IAT signal high would have PCM thinking the incoming air really cold right? When you did the compression test, what did the plugs look like?
Just replaced the plugs. Before this they had some gunk built up but they weren't too bad. I've got a new fuel pump for it as well. I don't know how the ECM deals with scanners so I can't say anything about the IAT.
 

unobtainium

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When you say "clear and try again" what do you mean exactly? Sorry I don't know much at all about EEC4.
 

rusty ol ranger

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You need a TPS sensor.

By clear and try again...he means clear the codes out, drive it a bit, and rescan to see whats come back
 

unobtainium

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OK I'll do that and let you know how it goes.
 

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I'm watching this. Got a similar problem. Runs good till it gets warmed up good, then starts that popping when on the throttle And looses power. Can't pull a small hill in 5th gear. It's a 90 model. No cat, new 02 sensor, new rotor/cap/wires/and plugs, new gray thing on side of distributor, timing checked, compression checked. I gave up on it and my son in law and grandson are now fighting it. Suggestions?
 

Brain75

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do you have identical codes?
 

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