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Car hesitating after it warms up!

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Old 07-18-2014, 09:38 AM
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usbutlermc
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Default Car hesitating after it warms up!

1992 lx runs fine for about 15-20 mins on the highway then it starts hesitating and sputtering when I hit the gas. Any ideas? Did a tune up not long ago and has been running fine until now. Car is drivable on my 45 min each way commute but problem seems to get worse the longer I drive. Car seems fine until it warms up. Need help. This is my daily driver.
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Old 07-18-2014, 10:00 AM
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88 orangepeel notch
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Pull codes, see what comes up. Maybe a bad ECT sensor. Do you have a fuel pressure gauge, or someway to check pressure? When was the last tune up done? Maybe TFI module starting to go. Could be alot of different things, just gotta narrow it down first by finding out if your losing spark or fuel.

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Old 07-18-2014, 02:10 PM
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Did a tune up a month ago. May have screwed something up but car was running fine for a month. Changed the plug wires out because one melted onto my header after I did the tune up. That didn't fix the hesitation problem though.
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Old 07-22-2014, 02:14 AM
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I had exactly the same problem after 30min of driving the car would die randomly and wouldn't start till after a few min of cooling tfi module would be your cause , any misfiring or surging would come from tfi module it detects the sparks n sets the timing but heat will make it go bad , if your car runs hot it'll mess em up I switched to a 160 thermostat so I don't fry them or buy a good brand tfi module you will need a special tool costs around 5$ to remove the two screws its located on the side of the distributor
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Old 07-25-2014, 09:56 AM
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Default Didn't work

Changed the tfi and the coil. Still same problem. Car runs fine until it heats up then it runs like crap and hesitates.
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Old 07-25-2014, 11:39 AM
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Js88lx
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It might be your PIP (dizzy) That was my issue! I also swapped out tfi and coil to no change! If yo buy a dizzy buy a new one not reman!! I did and it sucked kuzz it made me believe prob was something else but once I swapped dizzy AGAIN with a new one problem solved!
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Old 07-26-2014, 08:15 PM
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Default Cats

Is there any way that the cats being clogged could cause the problem. My center console and underneath the car seem to be really hot when the problem start occurring.
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Old 07-27-2014, 05:35 PM
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i strongly recommend doing a fuel pressure test , i just did mine last night turns out i had 28 psi and when under load droped to 22 or so i droped the gas tank was soo easy and replaced it now it has power it would start to bog down abit when warm , could be well worth to look into they loan them at autozone mabye your fuel pumps giving out low fuel pressure causing your car to run like crap, i didnt get a check engine light for low pressure never hurts to be sure other then that my car is running like a champ except for idle it moves around abit
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Old 07-27-2014, 05:37 PM
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if you need some details on how to drop gas tank incase your fuel pump is going bad let me know ill upload some info its easy 1-2hr job strongly recommend fuel pressure test
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Old 07-28-2014, 06:18 AM
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How do I do a fuel pressure test?
Originally Posted by fivepointohh666
i strongly recommend doing a fuel pressure test , i just did mine last night turns out i had 28 psi and when under load droped to 22 or so i droped the gas tank was soo easy and replaced it now it has power it would start to bog down abit when warm , could be well worth to look into they loan them at autozone mabye your fuel pumps giving out low fuel pressure causing your car to run like crap, i didnt get a check engine light for low pressure never hurts to be sure other then that my car is running like a champ except for idle it moves around abit
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