Idle like a rollercoaster
#1
Senior Member
Thread Starter
Join Date: Oct 2005
Location: England
Posts: 941
Likes: 0
Received 4 Likes
on
4 Posts
Car: 1987 GTA
Engine: 350 TPI w/ extras !
Transmission: 700R4
Idle like a rollercoaster
This is a problem a friend is having with her 3.1 Camaro. She's over 4 hours away so I can't just go round easily so I'm trying to get an idea of what could be going on.
She starts the car and the rpms sit pretty high even after the car has warmed up a bit. If she puts it in drive the rpms come crashing down and the car feels like it's about to cut out.
If she starts driving the car does indeed cut out!
My first thoughts could be the TPS? Or vacuum leaks. She can't read the codes or anything which doesn't help me either lol
She starts the car and the rpms sit pretty high even after the car has warmed up a bit. If she puts it in drive the rpms come crashing down and the car feels like it's about to cut out.
If she starts driving the car does indeed cut out!
My first thoughts could be the TPS? Or vacuum leaks. She can't read the codes or anything which doesn't help me either lol
#2
Member
Join Date: Apr 2018
Location: Atlanta, GA
Posts: 122
Received 39 Likes
on
29 Posts
Car: 1988 Pontiac Firebird
Engine: 2.8 L V6
Transmission: 700R4
Re: Idle like a rollercoaster
Check the timing first, but make sure you unplug the Distributor disconnect on the firewall. If the Disconnect isn't disconnected, the timing will be off by several degrees.
Also note, the #1 cylinder on the V6 is on the opposite side than a Small Block Chevy. As you are in England, I cannot identify the sides as Driver or Passenger, so it's best to check which cylinder is the leading cylinder. (Note, if the battery is in the same location as a North American 3.1 Camaro, it is generally easier to time the engine utilizing the #4 spark plug wire. This prevents the timing light pickup wire from crossing the serpentine system. As #4 cylinder fires 360 degrees out from #1 cylinder, the readings on the balancer will be the same.)
Also note, the #1 cylinder on the V6 is on the opposite side than a Small Block Chevy. As you are in England, I cannot identify the sides as Driver or Passenger, so it's best to check which cylinder is the leading cylinder. (Note, if the battery is in the same location as a North American 3.1 Camaro, it is generally easier to time the engine utilizing the #4 spark plug wire. This prevents the timing light pickup wire from crossing the serpentine system. As #4 cylinder fires 360 degrees out from #1 cylinder, the readings on the balancer will be the same.)
#3
Junior Member
Re: Idle like a rollercoaster
Tell your friend to run her hands along ever vacuum line that she can see, using a flashlight to check for holes and cracks. In particular, any lines which might make consistent contact with the engine because of how they’re routed.
Not sure if this is the *only* problem but you’ll find this is one of the most common solutions which is easy to diagnose with some time. Good luck!
Thread
Thread Starter
Forum
Replies
Last Post
Matro
Tech / General Engine
13
07-08-2013 09:15 AM