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Need Help with 87 running awful by Dad
Started on: 02-16-2014 07:53 PM
Replies: 15 (306 views)
Last post by: Csjag on 02-21-2014 07:51 PM
Dad
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Report this Post02-16-2014 07:53 PM Click Here to See the Profile for DadSend a Private Message to DadEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hi everyone. I am struggling with my daughters 87 v6-5speed. The car had been sitting in the garage for about 6 months with regular, every week or so start-ups. I did not drive it more than around the block so I did not notice when the current problem began. Here is the issue - The car runs well for the first 5 minutes or so after start when the battery has been disconnected, then when it is about at temperature the car begins to stumble and miss. Badly. If I disconnect the battery and wait a bit and then reconnect it, the car runs ok again for the same short time. What I have done so far- drained and refilled with fresh gas, removed and cleaned the Throttle body, changed the plugs, wires, distributor cap, rotor, Ignition Control Module, and today the entire distributor. It is running really well for the first few minutes, but then falls on its face. About 18 months ago I replaced the other Modules, EGR, EGR tube, and injectors. I don't know where to go next….I have no lights on the dash. Last weekend I saw a code for the Ignition Control module so I replaced it with a spare and then a brand new one. The light did not come back, but the issue remains. Just not sure what to do next- is this another module or maybe with the computer after it goes through the restart process. Any help would be much appreciated. I am running out of things to replace.
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Ventura
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Report this Post02-16-2014 07:59 PM Click Here to See the Profile for VenturaSend a Private Message to VenturaEdit/Delete MessageReply w/QuoteDirect Link to This Post
Replace the coolant temperature sensor located above the water pump.
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Gall757
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Report this Post02-16-2014 09:59 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
Welcome to the Forum!

The computer is taking over engine functions and is getting some bad information. I agree that the CTS is the primary suspect, but there are other possibilities. Are you saying your instrument panel lights don't work or you have no SES light?

[This message has been edited by Gall757 (edited 02-16-2014).]

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Dad
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Report this Post02-16-2014 10:13 PM Click Here to See the Profile for DadSend a Private Message to DadEdit/Delete MessageReply w/QuoteDirect Link to This Post
Sorry for the confusion. The dash is working and I have no codes in memory. I will order a CTS…please let me know if there are any other things to chase. Thanks again, Bill
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Csjag
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Report this Post02-16-2014 10:14 PM Click Here to See the Profile for CsjagClick Here to Email CsjagSend a Private Message to CsjagEdit/Delete MessageReply w/QuoteDirect Link to This Post
I think your problems are being caused by not giving the computer time to reset the engine after being powered down when you disconnect the battery. Try driving the car for 20 miles over 30 mph then turning it off for five minutes and then drive it again for another 20 miles, if you do this a few times the car should run better. If this doesn't help try some lucas gas additive you may have water or stale gas.
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Ventura
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Report this Post02-16-2014 10:31 PM Click Here to See the Profile for VenturaSend a Private Message to VenturaEdit/Delete MessageReply w/QuoteDirect Link to This Post
For what it's worth.....My '88 Formula ran fine for the first 5 minutes. Then after it warmed up it ran like Fido's butt because the CTS wasn't telling the ECM the correct engine temp. It ran rich and stumbled. Once I changed the CTS it ran great. Just my opinion.

[This message has been edited by Ventura (edited 02-16-2014).]

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Csjag
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Report this Post02-17-2014 06:50 AM Click Here to See the Profile for CsjagClick Here to Email CsjagSend a Private Message to CsjagEdit/Delete MessageReply w/QuoteDirect Link to This Post
Also check and make sure the antifreeze is full
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Csjag
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Report this Post02-17-2014 06:51 AM Click Here to See the Profile for CsjagClick Here to Email CsjagSend a Private Message to CsjagEdit/Delete MessageReply w/QuoteDirect Link to This Post

Csjag

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before yo buy a new cts check the wire connection to it also.
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IIKool
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Report this Post02-17-2014 08:03 AM Click Here to See the Profile for IIKoolClick Here to Email IIKoolSend a Private Message to IIKoolEdit/Delete MessageReply w/QuoteDirect Link to This Post
Somewhere on here, there is someone who knows how to do things in order to reset the computer.
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armos
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Report this Post02-17-2014 11:33 AM Click Here to See the Profile for armosSend a Private Message to armosEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Dad:
The car runs well for the first 5 minutes or so after start when the battery has been disconnected, then when it is about at temperature the car begins to stumble and miss. Badly. If I disconnect the battery and wait a bit and then reconnect it, the car runs ok again for the same short time.


It sounds like the problem temporarily goes away even if the engine is still warmed up, just from disconnecting the battery. In that situation, does it still run okay for 5 minutes, or does it drop to more like 30 seconds?

The ECM is always looking at the CTS. But it could still be the CTS, because when the ECM is in open loop (O2 sensor not yet up to temperature) it runs on the rich side. This could compensate for bad sensor readings, wherever they're coming from.
You can test the CTS with a multimeter:


If that checks out, what happens if you electrically unplug the O2 sensor? MAP sensor? (1 at a time)
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lou_dias
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Report this Post02-17-2014 02:34 PM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasEdit/Delete MessageReply w/QuoteDirect Link to This Post
With the battery disconnected, then reconnected, the IAC calibration needs to be done. This happens once the car is driven over 35 mph. Without that it won't idle right.
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theogre
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Report this Post02-17-2014 03:08 PM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreEdit/Delete MessageReply w/QuoteDirect Link to This Post
Have you put fresh gas in it?
Old gas can cause problem. Ethanol even worse.

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Dad
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Report this Post02-21-2014 07:29 PM Click Here to See the Profile for DadSend a Private Message to DadEdit/Delete MessageReply w/QuoteDirect Link to This Post
The sensor came in today and I just swapped it out. Reconnected the battery and the test drive showed the same problem. I have also noticed that the idle will fluctuate about 400 rpm say 1000-1400 after the problem starts. And it presenting itself under light throttle. If I push half way or so on the gas, she hesitates and then takes off and feels like normal. I am not sure what to try next. Fuel injectors, fuel filter (although having plenty of power when I give it throttle suggests it is not a delivery problem) maybe throttle body? She says she put in a bottle of fuel injector cleaner before it started, but I would think that would impact the filter. I don't know. I have no Check Engine light on and no codes. It is just running poorly. Anyone have any ideas?

Thanks, Dad
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Dad
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Report this Post02-21-2014 07:31 PM Click Here to See the Profile for DadSend a Private Message to DadEdit/Delete MessageReply w/QuoteDirect Link to This Post

Dad

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Sorry\- missed a post. Yes I have swapped out the gas- it is fresh stuff. Thanks

[This message has been edited by Dad (edited 02-21-2014).]

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BrittB
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Report this Post02-21-2014 07:50 PM Click Here to See the Profile for BrittBSend a Private Message to BrittBEdit/Delete MessageReply w/QuoteDirect Link to This Post
I would check the fuel pressure and if you haven't done it, fuel filter as well.
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Csjag
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Report this Post02-21-2014 07:51 PM Click Here to See the Profile for CsjagClick Here to Email CsjagSend a Private Message to CsjagEdit/Delete MessageReply w/QuoteDirect Link to This Post
Look at the engine while its running in the dark tonight and check and see if you can spot any arcing. Also wouldn't hurt to clean your grounds and even add a new ground.
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