(VIDEO) 87 NA hiccup/hesitation HELP
#1
Serotonin Satellite
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Erratic tach, terrible idle, hiccup, and hesitation. This happened while I was warming up my car a few weeks ago. It normally doesn't do this when I start the car. This is the worst I've ever seen it and captured it on video.
This issue happens 95% of the time while driving not while warming up and it cuts out so hard I feel like I just hit a brick wall at 10 MPH. Commonly happens around 2,500-4,000 RPMs. Somedays are better than others. Sometimes I can accelerate all the way to redline without a single hiccup. Other times I can get it passed 4,000 RPMs and have it hiccup closer to 6,000 RPMs and up.
Any ideas would be great. I've researched a lot and haven't really found this exact problem.
This issue happens 95% of the time while driving not while warming up and it cuts out so hard I feel like I just hit a brick wall at 10 MPH. Commonly happens around 2,500-4,000 RPMs. Somedays are better than others. Sometimes I can accelerate all the way to redline without a single hiccup. Other times I can get it passed 4,000 RPMs and have it hiccup closer to 6,000 RPMs and up.
Any ideas would be great. I've researched a lot and haven't really found this exact problem.
#3
Did you check the leading coil and trailing coils? Have you checked the grounds. Did you do anything to the car beforehand which might have contributed to this problem? Locate the Black bullet connector wire on the lead coil which connects to nothing and then find the same wire on the trailing coil and jumper these two wires together. This will cause the tach to work off of the leading coil and not the trailing coil. The coils also need to be grounded to the fender via contact so make sure they are both bolted to the fender properly and that the contact is clean between the coil bracket and the fender surface. If the ground is erratic or not present then the coils cannot work.
Last edited by satch; 03-02-13 at 01:43 PM.
#4
Serotonin Satellite
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Thread Starter
Did you check the leading coil and trailing coils? Have you checked the grounds. Did you do anything to the car beforehand which might have contributed to this problem? Locate the Black bullet connector wire on the lead coil which connects to nothing and then find the same wire on the trailing coil and jumper these two wires together. This will cause the tach to work off of the leading coil and not the trailing coil. The coils also need to be grounded to the fender via contact so make sure they are both bolted to the fender properly and that the contact is clean between the coil bracket and the fender surface. If the ground is erratic or not present then the coils cannot work.
#6
Serotonin Satellite
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Thread Starter
I replaced my fuel filter about a month ago, didn't notice any improvement.
I inspected and cleaned all the nuts, bolts, mounts, and brackets for both coils, also tried jumping them to run my tach off the other. Tach still glitches out and my car has no improvement.
I guess next step is to pull the fuel pump and test it... If that's not the issue then I guess I'll be forced to remove my intake manifold and get my injectors cleaned and balanced. And clean my ECU ground.
Anyone have any other ideas?
I inspected and cleaned all the nuts, bolts, mounts, and brackets for both coils, also tried jumping them to run my tach off the other. Tach still glitches out and my car has no improvement.
I guess next step is to pull the fuel pump and test it... If that's not the issue then I guess I'll be forced to remove my intake manifold and get my injectors cleaned and balanced. And clean my ECU ground.
Anyone have any other ideas?
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#9
Serotonin Satellite
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Thread Starter
#10
Serotonin Satellite
![](https://www.rx7club.com/images/misc/10_year_icon.png)
Thread Starter
Did you check the leading coil and trailing coils? Have you checked the grounds. Did you do anything to the car beforehand which might have contributed to this problem? Locate the Black bullet connector wire on the lead coil which connects to nothing and then find the same wire on the trailing coil and jumper these two wires together. This will cause the tach to work off of the leading coil and not the trailing coil. The coils also need to be grounded to the fender via contact so make sure they are both bolted to the fender properly and that the contact is clean between the coil bracket and the fender surface. If the ground is erratic or not present then the coils cannot work.
#11
W/the jumper in place, does the tach act sporadically as it did in the video or is that part better? Did you make sure the trailing coil was bolted to a clean fender surface? Did you check to see if the two electrical connectors to the coil were clean and solid?
Last edited by satch; 03-04-13 at 04:17 PM.
#12
Serotonin Satellite
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Thread Starter
The tach still glitches out. I cleaned all mounts and brackets with a wire blush and degreaser. The electrical connections were good.
#14
Serotonin Satellite
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#15
Serotonin Satellite
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A little update, I double checked my ECU ground and was able to get a finger on it.. It turns out its loose and very greasy/oily. Im going to try and clean the sh*t out of this ground and considering adding the pressure sensor ground mod for good measure.
Has anyone added the pressure sensor ground? I've heard it can be very effective.
Thanks
Has anyone added the pressure sensor ground? I've heard it can be very effective.
Thanks
#17
Serotonin Satellite
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Thread Starter
Issue resolved! All those hiccups and terrible spontaneous hesitation turned out to be just my ECU ground. Cleaned it up, bolted it to the factory location and problem solved!
Is there a detailed write up on the pressure sensor ground mod? I've only read very brief descriptions on what to do.. But nothing with detail or pictures...
Is there a detailed write up on the pressure sensor ground mod? I've only read very brief descriptions on what to do.. But nothing with detail or pictures...
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