84 hard start and stalling

[yitbos]

I've had my 84 at the dealership today and they are trying to figure out why it was hard to start and why it was stalling yesterday. I called and talked to the service person who told me the tech is still looking at it currently.

This is the same service representative I talked with yesterday when I dropped it off. He told me they know the following.

1. Yesterday, it smelled very rich. He had problems keeping it running while trying to move it around the shop.
2. It did not turn on the check engine light and has not registered any codes.

My question is can heat cause some of the stalling problems? It was 90+ degrees yesterday. I was stuck in a bumper-to-bumper traffic jam due to an accident and we were barely moving at all. When I got to the dealership, the interior of the car, below the center console armwrest and in the area between the driver and passenger was extremly warm.

Could the heat that was building up in there cause the fuel to boil or cause some other problem forcing the engine to run so rich? I'm really at a loss here. The dealership has had the car running in place for an hour they said without any problem at all. It was cold when they started it but it is not showing any of the symptoms from yesterday at all.

Any ideas from the online experts?
Thanks,
John

 

[JonM]

The fans don't come on until the engine reaches 238 degrees...and the transmission tunnel does get warm in stop and go traffic...I would check the TPS voltage it should be .5 at closed throddle. I would also remove and clean the 2 IAC Valves (Idle Air Control Valves).

I've had my 84 at the dealership today and they are trying to figure out why it was hard to start and why it was stalling yesterday. I called and talked to the service person who told me the tech is still looking at it currently.

This is the same service representative I talked with yesterday when I dropped it off. He told me they know the following.

1. Yesterday, it smelled very rich. He had problems keeping it running while trying to move it around the shop.
2. It did not turn on the check engine light and has not registered any codes.

My question is can heat cause some of the stalling problems? It was 90+ degrees yesterday. I was stuck in a bumper-to-bumper traffic jam due to an accident and we were barely moving at all. When I got to the dealership, the interior of the car, below the center console armwrest and in the area between the driver and passenger was extremly warm.

Could the heat that was building up in there cause the fuel to boil or cause some other problem forcing the engine to run so rich? I'm really at a loss here. The dealership has had the car running in place for an hour they said without any problem at all. It was cold when they started it but it is not showing any of the symptoms from yesterday at all.

Any ideas from the online experts?
Thanks,
John

 

[yitbos]

That is one thing I forgot to mention. I was watching the temp gauge and it was in the normal operating range. It kicks on at about 226 degrees and turns off around 218 degrees. So that part was working as it normally does for me.

John

 

[geekinavette]

If it runs ok cold, then goes terribly rich when warmed up...sounds like a possible CTS (Coolant Temp Sensor) culprit. What can happen is the ECM thinks the engine is cold all the time...and a cold engine needs a LOT more fuel than a warm engine, so the ECM just dumps a buttload (yes that is a technical term :L ) of fuel into the engine when it doesn't need it. This is the sensor in the front of the intake manifold...kinda buried behind the AIR valve assembly. The original sensor was a 1 wire unit, grounded through the threads of the sensor...the replacement is a 2 wire unit. If it still has the 1 wire original style just replace it regardless.

Bill

 

[yitbos]

Thanks for the input. The dealer still has it at the moment. I guess they are trying to duplicate the conditions to see if they can get the same failure. That is the first time it has been running and stalled. The gas smell was in the cabin and it would get very strong at times and then weak at other times.

I was really surprised there were no codes thrown at all though.

Plus, I didn't know the choke was electronic. SO I don't need to push on the gas peddle prior to starting the vehicle in the morning?

John

 

[geekinavette]

Who mentioned an electric choke? If it was the shop where it is now....then get it out of there NOW as they don't know what they're doing.

The '84 uses Electronic Fuel Injection...there is no choke!

Bill

 

[yitbos]

It was a comment in my previous post on the 84 being hard to start at times. Someone mentioned that and I replied in this post as it's an update to everything happening.

It's with a chevy dealer just up the street from my house. I hope they know what they are doing.

 

[WaveDoggie]

I had the exact same problem.

Solutions:
1. Install an 85 fuel pump. The 84 pump is merely adequate, and when it's not, fuel stalls in the lines and it indeed will vapor lock. Do this FIRST.

2. Replace the fan switch in the RH head with a 'Standard' Brand TS-217. This will get the fan running at 212F.

3. Check the gaskets betwen the air cleaner BASE to the COVER- the hood snoots are kinda useless when the air cleaner is sucking hot air off the manifold.