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2.5 Rough idle. hard start. Missing under acceleration. by Fats
Started on: 12-29-2014 05:17 PM
Replies: 9 (288 views)
Last post by: Zeak on 01-01-2015 02:52 AM
Fats
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Report this Post12-29-2014 05:17 PM Click Here to See the Profile for FatsClick Here to Email FatsSend a Private Message to FatsEdit/Delete MessageReply w/QuoteDirect Link to This Post
87 2.5.

Replaced the fuel pump yesterday.

Brand new battery today.

Hard to start, you almost have to feather the pedal to get it to start. Then feather it because it acts like it's missing a cylinder to idle. It never really smooths out, but it does get better. Driving down the road it acts like it's missing a cylinder, and any acceleration it "falls on its face."

It wasn't like this before the fuel pump left us... If it ever did. We figured it was at the very least extremely weak and not helping matters.

Brad

[This message has been edited by Fats (edited 12-29-2014).]

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pgold
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Report this Post12-29-2014 05:54 PM Click Here to See the Profile for pgoldClick Here to Email pgoldSend a Private Message to pgoldEdit/Delete MessageReply w/QuoteDirect Link to This Post
Have you replaced the fuel filter?
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Fats
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Report this Post12-29-2014 06:03 PM Click Here to See the Profile for FatsClick Here to Email FatsSend a Private Message to FatsEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yep, new filter as well.

Inside the tank was clean, but it was dumped out and fresh fuel put in. (Only sat around a month or so.)

Just went out to start it and it was hard to start, but idled just like it should after starting. I decided to let it run for a while and walked toward the house... It stuttered and went back to it's high/low almost dying idle, back to revving, almost dying. Ran like that for about 5 minutes, then died.

Brad
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Fats
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Report this Post12-29-2014 06:30 PM Click Here to See the Profile for FatsClick Here to Email FatsSend a Private Message to FatsEdit/Delete MessageReply w/QuoteDirect Link to This Post
Checked vacuum lines, can't locate any obvious leaks.

I did notice that the injector is spraying off and on, but I don't know if that is normal or not. Shouldn't it just be a steady stream?

ARRRGGGGGG

Brad
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jgrotzin
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Report this Post12-29-2014 08:58 PM Click Here to See the Profile for jgrotzinClick Here to Email jgrotzinSend a Private Message to jgrotzinEdit/Delete MessageReply w/QuoteDirect Link to This Post
Check the coil packs for cracks. While you're there check the crankshaft position sensor.
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Fats
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Report this Post12-29-2014 09:16 PM Click Here to See the Profile for FatsClick Here to Email FatsSend a Private Message to FatsEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by jgrotzin:

Check the coil packs for cracks. While you're there check the crankshaft position sensor.


ok. Thanks.

Brad
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mike-ohio
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Report this Post12-30-2014 09:05 PM Click Here to See the Profile for mike-ohioClick Here to visit mike-ohio's HomePageClick Here to Email mike-ohioSend a Private Message to mike-ohioEdit/Delete MessageReply w/QuoteDirect Link to This Post
Verify EGR is closing tight, will cause a big vacuum leak.

Check the coil packs and CPS.

always check plug wires not shorting.

Someone else had similar symptoms with a 87 duke and it was in the throttle body. Can't remember if it was a gasket or the IAC.

[This message has been edited by mike-ohio (edited 12-30-2014).]

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Fats
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Report this Post12-31-2014 06:44 PM Click Here to See the Profile for FatsClick Here to Email FatsSend a Private Message to FatsEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well, It'll start and run, it will kinda idle too. But put it into gear and it tries to die. This is not the TCC. I can idle down the road fine, feathering the fuel to keep it alive, but I try to speed up, or go up a hill and it starts missing and almost dying. Little backfires too.

Tomorrow I'm taking it to a shop, I can't properly diagnose it, and it needs to be fixed correctly. I don't want to just throw parts at it.

Thanks for all the help guys. +'s around.

Brad
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82-T/A [At Work]
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Report this Post12-31-2014 07:01 PM Click Here to See the Profile for 82-T/A [At Work]Send a Private Message to 82-T/A [At Work]Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Fats:

87 2.5.

Replaced the fuel pump yesterday.

Brand new battery today.

Hard to start, you almost have to feather the pedal to get it to start. Then feather it because it acts like it's missing a cylinder to idle. It never really smooths out, but it does get better. Driving down the road it acts like it's missing a cylinder, and any acceleration it "falls on its face."

It wasn't like this before the fuel pump left us... If it ever did. We figured it was at the very least extremely weak and not helping matters.

Brad




Hey Fats, my impression is that this is more than likely an ignition problem, either a crank position sensor, or your coil packs are going bad.

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Zeak
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Report this Post01-01-2015 02:52 AM Click Here to See the Profile for ZeakSend a Private Message to ZeakEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Fats:

Checked vacuum lines, can't locate any obvious leaks.

I did notice that the injector is spraying off and on, but I don't know if that is normal or not. Shouldn't it just be a steady stream?

ARRRGGGGGG

Brad


The injector for the 2.5 looks like an old shower head.....
(not mine)
Injector video

[This message has been edited by Zeak (edited 01-01-2015).]

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