New ZR-1. New Issue. Stalling Once Warm.

[Erik]

Don?t it always work that way. A few days into my ownership (or does she own me?) 996 started acting up.

For the first few days, I just took it easy. Was gonna get it in to the local Corvette guy for an inspection anyway. Started off with some short rides. As I got more comfortable, started expanding the range a bit. Finally was getting pretty comfortable so did some shopping, kicked a round a bit, and went and gave her a fresh tank of premium. Shortly after filling up, she coughed once. Not a backfire, but what felt like a fuel system cough. Meh, old gas working it?s way through, I thought. Got home ok. Parked for a while, and thought I?d taken her for a short run before dinner. As I?m toddling around, she coughs again. Then a few more times. Then a stall, starts up ok. Then does it a couple of more times. This is all slow speed, low gear, in the neighborhood stuff. Finally manage to nurse her home, and sent her off to the mechanic by flatbed to get the planned check over done.
Now, before the fresh tank of gas, she had run fine. Hadn?t pushed her to the redline yet, but 6000 rpm pulls felt good. Felt very smooth under power. Idle was ok. Seemed to want a couple of seconds cranking, but I?m used to modern cars that start so quickly, that the slightly longer cranking time might just be me.

Took her to the mechanic, and the good news is that all the mechanical stuff is good. Brakes, suspension. No oil leaks. Good structure. Nice, well kept car.

The bad news? It?s still doing the weird idle and coughing thing.

Here?s what it does:
-cold start. Starts up ok. Idles smoothly. No issues
-runs great until warm, then it starts running rough and wants to stall.
-give it gas. Keep it over 1000 rpm and it feels ok.

I had bought some parts for winter time projects, but it seemed a good idea to use them now. So, we replaced:

-Both fuel pumps, with New Delco ones. Socks, tee, etc
-Fuel filter
-spark plugs - just because. Idle smoothed out with new plugs in.

I spoke to Marc Haibeck on the weekend, and his first thought was fuel too.

Mechanic is gonna drain the tank today and see what it looks like in there. Not a lot of use over the past decade, so it could have a fair pit of crap inside.

Btw, the injectors were replaced by the previous owner.

Yes, when It was acting up, it sure felt like fuel. Maybe a bad carburetor?

Appreciate any thoughts.

[Erik]

And as luck would have it, my mechanics old, rarely used tech 1 decided to pack it in.

[Jagdpanzer]

Sounds like the primary fuel pump has failed. Same thing happened to my 94 which had seen a lot of storage before I acquired it.


Sent from my iPhone using ZR-1 Net Registry

[Erik]

Originally Posted by Jagdpanzer

Sounds like the primary fuel pump has failed. Same thing happened to my 94 which had seen a lot of storage before I acquired it.


Sent from my iPhone using ZR-1 Net Registry

Thanks, Phil.

Which I figured would happen too. But we swapped it out with a new one, and it's still doing the same thing.

He will delve into the tank today, and see what the bottom of it looks like!

[BigJohn]

Y?all have changed fuel filters?
Some times crud from bottom of fuel tank.

[Erik]

Originally Posted by BigJohn

Y?all have changed fuel filters?
Some times crud from bottom of fuel tank.

Yup. The fuel filter got changed the same time as the pumps did. They will be cleaning out the bottom of the tank today.

Thanks, BigJohn

[-=Jeff=-]

While I don't have a Tech 1. I am using ALDLDroid and TunerPro to log data from my 1990. it is great to see many things at once. that might help for troubleshooting the problem. especially if it is happening as soon as it goes into closed loop. A fresh set of o2 sensors might help as well

[Erik]

Originally Posted by -=Jeff=-

While I don't have a Tech 1. I am using ALDLDroid and TunerPro to log data from my 1990. it is great to see many things at once. that might help for troubleshooting the problem. especially if it is happening as soon as it goes into closed loop. A fresh set of o2 sensors might help as well

Hi Jeff.
What do you use to connect your phone or computer to your car? A USB to OBD1 connector of some kind?

[-=Jeff=-]

OH yeah that info will help. LOL

I have a USB to ALDL cable that I typically use.. forget where I got it

I also have a Bluetooth adapter:
http://www.1320electronics.com/12pin_ALDL_BT_MK2.html

other use this one Bluetooth adapter
http://www.reddevilriver.com/ALDL_Bluetooth.html

they also sell the USB to ALDL
http://www.reddevilriver.com/aldl.html

for ALDLDroid, it is only avail for android. I use a Nexus7 Tablet..

[Erik]

Originally Posted by -=Jeff=-

OH yeah that info will help. LOL

I have a USB to ALDL cable that I typically use.. forget where I got it

I also have a Bluetooth adapter:
http://www.1320electronics.com/12pin_ALDL_BT_MK2.html

other use this one Bluetooth adapter
http://www.reddevilriver.com/ALDL_Bluetooth.html

they also sell the USB to ALDL
http://www.reddevilriver.com/aldl.html

for ALDLDroid, it is only avail for android. I use a Nexus7 Tablet..

Any preference between the 1320 Electronics stuff and the Red Devil River?

Looks like the Bluetooth version would be the one to get. Does it stay connected well? The price difference at Red Devil River is pretty small. I have old Android devices kicking around that I can put to use.

Or, is there a good reason for using something like a laptop?

Thanks! This is awesome info!