2nd Generation Specific 1986-1992 Discussion

hesistation at 4000 rpms

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Old 10-21-2002 | 10:24 PM
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Would anyone know why my car slows dramatically when i hit 4000 rpms I still get boost till i get to 4000 but i thought it might be a bad cat but i punched my cat out and it still did it. I seems to go away after i drive for a while and then i comes back and starts hesistating again. I have asked people but no one can figure it out. I have a 87 turbo 2. If anyone tell me what is up, let me know. thanks

jason
Old 10-21-2002 | 10:35 PM
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check all your grounds if those check out possibly something wrong with your ecu or secondary fuel injectors



i'm moving this to the 2nd gen forum
Old 10-22-2002 | 09:55 AM
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Mine's an N/A, and stutters at 3800rpm, someone told me that was common, and that I needed to "reground my ECU," which I have yet to figure out how.
Old 10-22-2002 | 10:31 AM
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Originally Posted by Baldy' date='Oct 22 2002, 08:55 AM
Mine's an N/A, and stutters at 3800rpm, someone told me that was common, and that I needed to "reground my ECU," which I have yet to figure out how.
I think they mean what vosko said, Reground all the grounds on the wiring harness. I would have to go check but i know there is 1 going from the engine to the firewall near the windshield wiper motor. There is one going to the tranny near the slave cylinder also i believe. There is on on the block also right under the dynamic chamber too. Just go along the wiring harness and looks for grounds. Put in new bigger wires and make sure the contact area is free from paint, bare metal.
Old 10-22-2002 | 10:34 AM
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Originally Posted by vosko' date='Oct 21 2002, 09:35 PM
check all your grounds if those check out possibly something wrong with your ecu or secondary fuel injectors



i'm moving this to the 2nd gen forum
yup, its either bad grounds, ecu, the wiring harness, or the secondary injectors.
Old 10-22-2002 | 10:37 AM
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Baldy...bout the N/A...Mine was diong the same exact thing. it was the secondary injectors. the plug for them didnt have good contact. i cleaned them and cleaned the secondary actuators, and i never had the problem again...



my car would just studder at about 3800-4000rpms. if i would baby the gas, it would go through and at about 5-6krpms it would get better...
Old 10-22-2002 | 12:06 PM
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the problem ground is the one under the intake, on top of the motor.



mike
Old 10-22-2002 | 12:31 PM
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Originally Posted by YucA' date='Oct 22 2002, 09:37 AM
Baldy...bout the N/A...Mine was diong the same exact thing. it was the secondary injectors. the plug for them didnt have good contact. i cleaned them and cleaned the secondary actuators, and i never had the problem again...



my car would just studder at about 3800-4000rpms. if i would baby the gas, it would go through and at about 5-6krpms it would get better...
You'll have to pardon my stupidness....this shows how much I know about these cars: Where are the secondary actuators, and what do they do? I understand the plugs and wires, but I'm still getting used to the terminology with the rotaries.
Old 10-22-2002 | 02:54 PM
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Originally Posted by j9fd3s' date='Oct 22 2002, 11:06 AM
the problem ground is the one under the intake, on top of the motor.



mike
So the ground underneath the intake manifold causes this? Ive been having this problem for so long I cant remember what taking it to redline feels like. Is there any way you can post a pic of that ground or explain in detail where the ground comes from? Thanks
Old 10-22-2002 | 02:59 PM
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Originally Posted by Baldy' date='Oct 22 2002, 11:31 AM
[quote name='YucA' date='Oct 22 2002, 09:37 AM']Baldy...bout the N/A...Mine was diong the same exact thing. it was the secondary injectors. the plug for them didnt have good contact. i cleaned them and cleaned the secondary actuators, and i never had the problem again...



my car would just studder at about 3800-4000rpms. if i would baby the gas, it would go through and at about 5-6krpms it would get better...
You'll have to pardon my stupidness....this shows how much I know about these cars: Where are the secondary actuators, and what do they do? I understand the plugs and wires, but I'm still getting used to the terminology with the rotaries.[/quote]

Baldy, the secondary injectors are directly underneath the upper intake manifold and require you to take it off to access them. The secondary injectors give more fuel when the engine is under load at 3800 rpms. So if power is not there at or around 3800 and on, it could be the secondary injectors.



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