Idle is rough 1986
Thread Starter
Cruising
Joined: Jun 2011
Posts: 14
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Idle is rough 1986
It idles very rough much worse with the ac on. I tried to pull the codes but all that happens is the check engine light just keeps flashing. Tied cleaning the throttle body and it got worse. Could it be a stuck injector. It is very annoying.
One weird thing when I tried to pull the codes and ground A and B the fan comes on not sure if that is supposed to happen.
One weird thing when I tried to pull the codes and ground A and B the fan comes on not sure if that is supposed to happen.
Burning Brakes
Joined: May 2011
Posts: 838
Likes: 2
From: Louisville Ky
It idles very rough much worse with the ac on. I tried to pull the codes but all that happens is the check engine light just keeps flashing. Tied cleaning the throttle body and it got worse. Could it be a stuck injector. It is very annoying.
One weird thing when I tried to pull the codes and ground A and B the fan comes on not sure if that is supposed to happen.
One weird thing when I tried to pull the codes and ground A and B the fan comes on not sure if that is supposed to happen.
most idle issues are vac leaks, check all vac lines you can see, use a piece of long hose as a listening device, for hissing.
Thread Starter
Cruising
Joined: Jun 2011
Posts: 14
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It hesitates a little when you gas it hard but seems to run smooth just driving it down the road.
Instructor
Joined: Jun 2011
Posts: 182
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From: Bowling Green Ky
try spraying carb cleaner into throttle body, engine off, use cloth rags to wipe the carbon off inside, around throttles of course. can use it with engine running also.
the obvious stuff, clean air filter, can remove the snorkel tube to see if it makes difference. some vac lines run all way to fuel tank, around battery area and get deteriotated by the fumes.
the obvious stuff, clean air filter, can remove the snorkel tube to see if it makes difference. some vac lines run all way to fuel tank, around battery area and get deteriotated by the fumes.
Thread Starter
Cruising
Joined: Jun 2011
Posts: 14
Likes: 0
try spraying carb cleaner into throttle body, engine off, use cloth rags to wipe the carbon off inside, around throttles of course. can use it with engine running also.
the obvious stuff, clean air filter, can remove the snorkel tube to see if it makes difference. some vac lines run all way to fuel tank, around battery area and get deteriotated by the fumes.
the obvious stuff, clean air filter, can remove the snorkel tube to see if it makes difference. some vac lines run all way to fuel tank, around battery area and get deteriotated by the fumes.
Slingshot
Joined: Dec 2001
Posts: 3,817
Likes: 24
From: Charlotte NC
Also, you need to fill out your User Profile which will allow the Forum member to better help you.
Last edited by pmihaltian; Jul 4, 2011 at 02:59 PM.
Instructor
Joined: Jun 2011
Posts: 182
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From: Bowling Green Ky
prob is not fuel filter or you see that at running rpm. if it stumbles on accelleration, could be.
spark plugs and wires are related to idle issues. the carb spray should not make it worse except when wet, if engine running.
if you think of teh recent history, changes you may have caused, that is a clue.
Thread Starter
Cruising
Joined: Jun 2011
Posts: 14
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Its a 1986 l98 alumman heads. I tried to pull the codes and nothing came up the only thing that happened was the check engine would blink three times wait then blink again.
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Instructor
Joined: Jun 2011
Posts: 182
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From: Bowling Green Ky
count the blinks. one three times, 2 three times is 12, etc. record what they are until it returns to 12. post.
Burning Brakes
Joined: May 2011
Posts: 838
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From: Louisville Ky
If you have not a factory service MAnual, FSM, or the Haynes manual you are lost. you can search here for how to pull codes and how NOT to do it. The light blinking is the code.
Thread Starter
Cruising
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Racer
Joined: Apr 2010
Posts: 285
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From: New Prague MN
Thats a code 34, Mass Air Flow Sensor. You may have set it off when you pulled the snorkel off. Clear the code by disconnecting your negative battery cable for 5 to 10 minutes. Hook the battery back up, take a drive or let it run a while and see if you get another code to set.
Thread Starter
Cruising
Joined: Jun 2011
Posts: 14
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Thats a code 34, Mass Air Flow Sensor. You may have set it off when you pulled the snorkel off. Clear the code by disconnecting your negative battery cable for 5 to 10 minutes. Hook the battery back up, take a drive or let it run a while and see if you get another code to set.
Racer
Joined: Apr 2010
Posts: 285
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From: New Prague MN
It can, but I would do further diagnostics before I throw 150+ at a maybe. I am chasing the same problem on my 86 right now but am convinced it is a vac problem. They can just be very tough to find. Lots of 26 year old hard, brittle plastic lines. It could be that your EGR valve is stuck open. From what I understand that is a common problem.
Thread Starter
Cruising
Joined: Jun 2011
Posts: 14
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It can, but I would do further diagnostics before I throw 150+ at a maybe. I am chasing the same problem on my 86 right now but am convinced it is a vac problem. They can just be very tough to find. Lots of 26 year old hard, brittle plastic lines. It could be that your EGR valve is stuck open. From what I understand that is a common problem.
Thread Starter
Cruising
Joined: Jun 2011
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Ok I am thinking it may be the relays, I went out and unpluged wires cleaned them banged on the relays and it worked for a while. I guess trying relays first is alot cheaper then buying the maf.
Racer
Joined: Apr 2010
Posts: 285
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From: New Prague MN
Good idea. Relays are 15 to 17 each vs 150 for a MAF. Just priced that stuff out myself yesterday (just in case).
Burning Brakes
Joined: May 2011
Posts: 838
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From: Louisville Ky