88 4.0 backfires when I connect the MAP to vacuum
#16
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Hey DJ,
Yes, it's true. I did reuse the gasket. The weekend I was reassembling I couldn't get a new one and didn't go back and replace it.
Just added to list.
I'm grasping at straws here but could that cause my strange MAP issue?
Thanks,
Jeff
Yes, it's true. I did reuse the gasket. The weekend I was reassembling I couldn't get a new one and didn't go back and replace it.
Just added to list.
I'm grasping at straws here but could that cause my strange MAP issue?
Thanks,
Jeff
#17
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With it idling spray carb cleaner along the area where the intake mates to the head.
That will snswer some questions.
That will snswer some questions.
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SOLVED.
I put #1 on TDC. Modified my Dizzy. Advanced the timing. Connect the MAP. Drove it around for a few miles and it ran better than ever.
No backfires. No anything.
Still runs a little rough but my 746s arrived today so they go in tomorrow and they should help smooth out the remaining roughness. Still drops too low (idle) between gears sometimes (even dies some) but calibrating the TPS is still on my list (it's actually #8 on my list). LOL
Thanks Everyone for all the great input,
p.s. I sprayed a liberal amount of carb cleaner around the intake gasket while it was running and got no change in idle at all. The old gasket must have sealed it pretty well. I have a new gasket but will wait till I'm taking off the Intake for something else and change it then.
I put #1 on TDC. Modified my Dizzy. Advanced the timing. Connect the MAP. Drove it around for a few miles and it ran better than ever.
No backfires. No anything.
Still runs a little rough but my 746s arrived today so they go in tomorrow and they should help smooth out the remaining roughness. Still drops too low (idle) between gears sometimes (even dies some) but calibrating the TPS is still on my list (it's actually #8 on my list). LOL
Thanks Everyone for all the great input,
p.s. I sprayed a liberal amount of carb cleaner around the intake gasket while it was running and got no change in idle at all. The old gasket must have sealed it pretty well. I have a new gasket but will wait till I'm taking off the Intake for something else and change it then.
#20
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SOLVED.
I put #1 on TDC. Modified my Dizzy. Advanced the timing. Connect the MAP. Drove it around for a few miles and it ran better than ever.
No backfires. No anything.
Still runs a little rough but my 746s arrived today so they go in tomorrow and they should help smooth out the remaining roughness. Still drops too low (idle) between gears sometimes (even dies some) but calibrating the TPS is still on my list (it's actually #8 on my list). LOL
Thanks Everyone for all the great input,
p.s. I sprayed a liberal amount of carb cleaner around the intake gasket while it was running and got no change in idle at all. The old gasket must have sealed it pretty well. I have a new gasket but will wait till I'm taking off the Intake for something else and change it then.
I put #1 on TDC. Modified my Dizzy. Advanced the timing. Connect the MAP. Drove it around for a few miles and it ran better than ever.
No backfires. No anything.
Still runs a little rough but my 746s arrived today so they go in tomorrow and they should help smooth out the remaining roughness. Still drops too low (idle) between gears sometimes (even dies some) but calibrating the TPS is still on my list (it's actually #8 on my list). LOL
Thanks Everyone for all the great input,
p.s. I sprayed a liberal amount of carb cleaner around the intake gasket while it was running and got no change in idle at all. The old gasket must have sealed it pretty well. I have a new gasket but will wait till I'm taking off the Intake for something else and change it then.
Did you INDEX the distributor? You can't advance the timing.
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Oh yeah. Right thing. Wrong terms.
I followed a very detailed, step by step walk through that some old dude named Cruiser wrote up.
Seems to know what he's talking about but you never know, right?
I followed a very detailed, step by step walk through that some old dude named Cruiser wrote up.
Seems to know what he's talking about but you never know, right?
![Whistling2](https://www.cherokeeforum.com/images/smilies/whistling2.gif)
#22
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Okay,
So I've been reading about adjusting the TPS. I have my soldering iron laid out for tuning up that sensor harness. I have a question about Throttle body cleaner. A friend swears by Sea Foam but I think I read some disparaging comments about it on here. I have a can of CRC but wonder what the thoughts are on Sea Foam.
I just want to be sure I get a good clean up prior to adjusting the TPS.
BTW, just want to go on record as a raving fan of Cruiser's write ups. Top notch info and easy to follow. I can't be the only one who feels that way.
Thanks Cruiser!
So I've been reading about adjusting the TPS. I have my soldering iron laid out for tuning up that sensor harness. I have a question about Throttle body cleaner. A friend swears by Sea Foam but I think I read some disparaging comments about it on here. I have a can of CRC but wonder what the thoughts are on Sea Foam.
I just want to be sure I get a good clean up prior to adjusting the TPS.
BTW, just want to go on record as a raving fan of Cruiser's write ups. Top notch info and easy to follow. I can't be the only one who feels that way.
Thanks Cruiser!
#23
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It's all mythical... He's a crazy old fart spouting nonsense every chance he gets.....
#24
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Okay,
So I've been reading about adjusting the TPS. I have my soldering iron laid out for tuning up that sensor harness. I have a question about Throttle body cleaner. A friend swears by Sea Foam but I think I read some disparaging comments about it on here. I have a can of CRC but wonder what the thoughts are on Sea Foam.
I just want to be sure I get a good clean up prior to adjusting the TPS.
BTW, just want to go on record as a raving fan of Cruiser's write ups. Top notch info and easy to follow. I can't be the only one who feels that way.
Thanks Cruiser!
So I've been reading about adjusting the TPS. I have my soldering iron laid out for tuning up that sensor harness. I have a question about Throttle body cleaner. A friend swears by Sea Foam but I think I read some disparaging comments about it on here. I have a can of CRC but wonder what the thoughts are on Sea Foam.
I just want to be sure I get a good clean up prior to adjusting the TPS.
BTW, just want to go on record as a raving fan of Cruiser's write ups. Top notch info and easy to follow. I can't be the only one who feels that way.
Thanks Cruiser!
Do Tip 5, make mods to the harness as indicated by that. clean the throttle body. Adjust TPS on engine side per the Tip.
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Okay,
So I've been reading about adjusting the TPS. I have my soldering iron laid out for tuning up that sensor harness. I have a question about Throttle body cleaner. A friend swears by Sea Foam but I think I read some disparaging comments about it on here. I have a can of CRC but wonder what the thoughts are on Sea Foam.
I just want to be sure I get a good clean up prior to adjusting the TPS.
BTW, just want to go on record as a raving fan of Cruiser's write ups. Top notch info and easy to follow. I can't be the only one who feels that way.
Thanks Cruiser!
So I've been reading about adjusting the TPS. I have my soldering iron laid out for tuning up that sensor harness. I have a question about Throttle body cleaner. A friend swears by Sea Foam but I think I read some disparaging comments about it on here. I have a can of CRC but wonder what the thoughts are on Sea Foam.
I just want to be sure I get a good clean up prior to adjusting the TPS.
BTW, just want to go on record as a raving fan of Cruiser's write ups. Top notch info and easy to follow. I can't be the only one who feels that way.
Thanks Cruiser!
#26
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