Where to start?
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Joined: Feb 2014
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Where to start?
Hi,
My 86 engine started acting strange and I am trying to figure out where to begin with diagnosis. It seems to idle fine and run down the road at steady rpm ok. When I accelerate though it starts missing badly. When idling there is a very noticeable tapping sound on the top of the engine. I did the old wooden stick to ear trick and the noise is coming, most pronounced, from the aluminum rail across the top of the engine, not from the valve covers or dist cap. How much trouble am I in? Thank you!
My 86 engine started acting strange and I am trying to figure out where to begin with diagnosis. It seems to idle fine and run down the road at steady rpm ok. When I accelerate though it starts missing badly. When idling there is a very noticeable tapping sound on the top of the engine. I did the old wooden stick to ear trick and the noise is coming, most pronounced, from the aluminum rail across the top of the engine, not from the valve covers or dist cap. How much trouble am I in? Thank you!
Last edited by 86couper; May 26, 2016 at 07:53 AM. Reason: Add info
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The tapping noise your hearing is the injectors Firing. Normally they can sound like a mal adjusted lifter.
Your symptoms of bad acceleration can be one of many. Might take a bit of time to narrow to the real problem. Starting with fuel, can you measure the fuel pressure? Both idling and accelerating.
You can also check the fuel pressure regulator by pulling the vaccum line off and smelling for the presence of raw fuel. Should this be the case, you need to replace the FPR immediately.
Your symptoms of bad acceleration can be one of many. Might take a bit of time to narrow to the real problem. Starting with fuel, can you measure the fuel pressure? Both idling and accelerating.
You can also check the fuel pressure regulator by pulling the vaccum line off and smelling for the presence of raw fuel. Should this be the case, you need to replace the FPR immediately.
Last edited by JrRifleCoach; May 27, 2016 at 12:42 AM.
Team Owner
Joined: Jan 2003
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From: Summerland B.C. Canada
The tapping noise your hearing is the injectors Firing. Normally they can sound like a mal adjusted lifter.
Your symptoms of bad acceleration can be one of many. Might take a bit of time to narrow to the real problem. Starting with fuel, can you measure the fuel pressure? Both idling and accelerating.
You can also check the fuel pressure regulator by pulling the vaccum line off and smelling for the presence of raw fuel. Should this be the case, you need to replace the FPR immediately.
Your symptoms of bad acceleration can be one of many. Might take a bit of time to narrow to the real problem. Starting with fuel, can you measure the fuel pressure? Both idling and accelerating.
You can also check the fuel pressure regulator by pulling the vaccum line off and smelling for the presence of raw fuel. Should this be the case, you need to replace the FPR immediately.
Start with fuelWhen was your last fuel filter change ?
Do you have a pressure gauge ?
Thread Starter
Advanced
Joined: Feb 2014
Posts: 54
Likes: 0
The tapping noise your hearing is the injectors Firing. Normally they can sound like a mal adjusted lifter.
Your symptoms of bad acceleration can be one of many. Might take a bit of time to narrow to the real problem. Starting with fuel, can you measure the fuel pressure? Both idling and accelerating.
You can also check the fuel pressure regulator by pulling the vaccum line off and smelling for the presence of raw fuel. Should this be the case, you need to replace the FPR immediately.
Your symptoms of bad acceleration can be one of many. Might take a bit of time to narrow to the real problem. Starting with fuel, can you measure the fuel pressure? Both idling and accelerating.
You can also check the fuel pressure regulator by pulling the vaccum line off and smelling for the presence of raw fuel. Should this be the case, you need to replace the FPR immediately.
Thread Starter
Advanced
Joined: Feb 2014
Posts: 54
Likes: 0
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