Non-smotth idle
Thread Starter
Intermediate
Joined: Feb 2003
Posts: 29
Likes: 0
From: Zurich
Non-smotth idle
Hi everybody
Yesterday for the first time I encountered a not completely smooth idle. I have nothing changed for months so I do not expect to have an effect of some of my mods (C5 1998 model, Hypertech III, Beru plugs, Z06 intake manifold, MAF from West coast corvette, Ram air vortex intake).
The problems is as follows: my idle goes smooth for approximately 30 seconds and then there is an interruption - I had my lights on so you could actually see that the light became weaker. It feels like a short "break"/stop in the electrical system. Has anybody of you encoutered such a problem or do you have any idea what it could be and how to resolve it? Thanks a lot for you help.
Andreas
Yesterday for the first time I encountered a not completely smooth idle. I have nothing changed for months so I do not expect to have an effect of some of my mods (C5 1998 model, Hypertech III, Beru plugs, Z06 intake manifold, MAF from West coast corvette, Ram air vortex intake).
The problems is as follows: my idle goes smooth for approximately 30 seconds and then there is an interruption - I had my lights on so you could actually see that the light became weaker. It feels like a short "break"/stop in the electrical system. Has anybody of you encoutered such a problem or do you have any idea what it could be and how to resolve it? Thanks a lot for you help.
Andreas
Drifting
Joined: Jul 2002
Posts: 1,386
Likes: 80
From: NC
Cruise-In IV Veteran
St. Jude Contributor
Re: Non-smotth idle (aschon)
Do you still have your stock MAF? You may try to put the stock MAF on to see if the problem corrects itself.
Your 98 C5 can possibly benefit from an aftermarket MAF, but I have only seen successful MAF upgrades when LS1 Edit is used to modify the the PCM's MAF tables. Your aftermarket MAF may not be working too well with the stock PCM MAF tables.
Your 98 C5 can possibly benefit from an aftermarket MAF, but I have only seen successful MAF upgrades when LS1 Edit is used to modify the the PCM's MAF tables. Your aftermarket MAF may not be working too well with the stock PCM MAF tables.
Racer
Joined: Dec 2001
Posts: 376
Likes: 0
From: BLMVOR R160 [] HOCVOR R305 Switzerland BL
Re: Non-smotth idle (aschon)
Hi Andreas
What a nice surprise to read you here as well. But I deeply regret to see you struggled with this unfortunate electronic/electric Gremlin.
You might verify and consider the following :
=> check all seatings : SP-Wires, both ends o/t connectors for correct seating on their respective lieus
=> check all the little threaded top nuts of the S-Plugs for ev. looseness
=> check for correct torque of the S-Plugs
Other possibilities in question seem harder to verify, as e.g.
=> IAC = Idle Air Control Circuitry
=> Ignition Coil's malfunction, especially when the engine sees operational temps
=> check at least all Ignition Coils for overall correctly tightened cable linkages (all of the ground-straps)
Last but certainly not least : you might check-out for engine related DTCs stored on the IPC/DIC. Sorry for being not more factual to your troubles, but, nevertheless, I do hope my advises could assist to move fwd.
Good luck Andreas !! Please let us know your findings !!
Joe. :seeya see u soon !! :steering: :cheers:
What a nice surprise to read you here as well. But I deeply regret to see you struggled with this unfortunate electronic/electric Gremlin.
You might verify and consider the following :
=> check all seatings : SP-Wires, both ends o/t connectors for correct seating on their respective lieus
=> check all the little threaded top nuts of the S-Plugs for ev. looseness
=> check for correct torque of the S-Plugs
Other possibilities in question seem harder to verify, as e.g.
=> IAC = Idle Air Control Circuitry
=> Ignition Coil's malfunction, especially when the engine sees operational temps
=> check at least all Ignition Coils for overall correctly tightened cable linkages (all of the ground-straps)
Last but certainly not least : you might check-out for engine related DTCs stored on the IPC/DIC. Sorry for being not more factual to your troubles, but, nevertheless, I do hope my advises could assist to move fwd.
Good luck Andreas !! Please let us know your findings !!
Joe. :seeya see u soon !! :steering: :cheers:
Heel & Toe
Joined: Sep 2003
Posts: 16
Likes: 0
From: Abilene Tx
Re: Non-smotth idle (aschon)
Well I actually took off my SLP MAF and put the stock one back on, it still does the same thing, it also runs erratic, one day it will run great the next it will run really crappy, ie not much rubber will be left on the road, almost always under the same conditions. Any thoughts anyone...?
Bill :cheers:
Bill :cheers:
Instructor
Joined: Jan 2003
Posts: 247
Likes: 0
From: El Paso TX
Re: Non-smotth idle (aschon)
Mine surged and dropped...750-1200-750-450-750-1200rpm...several times a minute. The problem was the PCV return hose was "sucking air". Had the hose replaced and worked perfectly :yesnod:
Thread Starter
Intermediate
Joined: Feb 2003
Posts: 29
Likes: 0
From: Zurich
Re: Non-smotth idle (bgood)
Thanks for the tip with the LS1 Edit. Unfortuantely, there I don't no anybody here in Switzerland who could do a LS1 Edit reprogramming for a 1998 model. Do you think I could do this myself? Is there any information available on this?
Best regards,
Andreas
Best regards,
Andreas
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