John M

Hi All,
New guy here with my first Chevy Van. Have had Fords and Dodges up until now.

So, I found this 93 G30 van that a guy was using for a storage unit on his property. It hadn't been on the road for about 5 years, though he started it up and moved it around a couple of times a year. It has the 350, auto trans in it and about 119,000 miles. Decent shape, needed tires and a battery. I drove the van this past summer and noticed that when it is real damp out,, that the van is hard starting. The more damp, the harder to start. On a dry day, just reach in and hit the key, it's running.

We got our first snow this week, and it has been nearly impossible to start the past few days. I turn the key on, wait for the pump to pressurize, and turn it over. It will turn a few times and then fire, but won't catch. If I push the accelerator part way down, it will fire more, but still won't catch. So, I keep doing it and if I leave it spin with the accelerator half way down or so, the firing will come closer and closer together and finally take off and run. Then it smokes black and smells like fuel... so obviously ( I think?) it's flooding. Yet, when I don't step on the pedal, it won't catch and start out... just spins and fires. Once it starts, it runs great, gets great mileage, etc.

The first time this wouldn't start, I pulled the doghouse and checked the cap and rotor. The cap looked pretty new, no corrosion inside and appeared to be dry. No sign of condensation at all. I checked all wires and such looking for something conspicuous that could be wrong and still no fire. I took an electric heater with a fan and put it in the engine compartment and ran it for about an hour or so, and then it started. This weekend now, with cold damp snowing, I can't get it to run at all. I actually have a propane heater blowing air into the engine compartment trying to see if that will help get it running.

Is this an issue with these vans? I've seen vehicles in the past that didn't like damp weather, but nothing this bad. Is there something that I can do to alleviate this problem? Any help would be greatly appreciated.

Thanks in advance, John

canucklehead

Worn spark plugs or gaps that are too big can cause hard cold starting. Once my 2002 express vortec 350 fired then stalled when cold and would not fire again. I checked all the things you did, and then I got a wrench and pulled one of the back plugs that you can get from inside.....tapped the plug on the block to close the gap and bit, and put it back. Fired right up. After I bought a new set of Iridium plugs and it never happened again.
Also, even though it sounds like a spark issue, check the injectors....The secondary injector is also the cold start one. It could be dribbling fuel and not spraying it. They can be swapped as they are the same.

John M

Thanks for the quick reply. Forgot to mention that I did put new plugs in and it made no difference, although I did not install AC Delco plugs. Not sure if that will make a difference or not? I used NGK plugs.

This has a TBI system. Is there still a secondary injector?

Thanks again, John

canucklehead

The top of the throttle body has 2 injectors right at the top. One is the primary, and the other is the secondary.

http://www.truckforum.org/attachment...0317-jpg.1815/

Have you checked for any codes?

John M

I haven't checked for codes. The check engine light is not on.

Yesterday I put a propane heater under the engine and let it run for about a half hour or so. Then I was able to get the van running. Once it starts up, it runs great. We have rain and fog this morning so I expect it may have trouble starting again. In fact, I'd be more surprised if it does start than if it didn't!

I don't have a code checker for the older vehicles, can the codes be retrieved by jumping the two wires in the plug?

Thanks again for your direction.

canucklehead

You could also check the ground strap, and take some time to clean up all the contacts around the battery

John M

So, to update and add some more info.

The guy I got this from said that when he would start it, he would turn the key on and pump the accelerator 10 times and then it would start. I did that as well for awhile, then found after using it a few weeks, that it started fine not doing that- as long as it wasn't damp out. All summer long when I would start it, I'd just turn the key and it would start up. Now that we are into the cold damp snow season, it's getting nearly impossible to start.

If I go out to start it, and just turn the key, it spins and spins and won't fire at all.

If I turn the key on and pump the pedal a few times and let off of the pedal, it will fire about every tenth revolution or so, but won't catch and run.

If I keep the pedal about half way down or so, the firing will come closer, but still won't won't catch and run.

I'll often have to vary between keeping the pedal all the way to the floor, and half way down to get it running.It takes probably a good 5 minutes of actual turning it over until it actually starts, and then the tail pipe smokes black until the engine clears out. So, it's getting too much fuel in the system from pumping the gas pedal? But if I don't pump it , it won't fire at all.

Could the converter be partially plugged?
My wife says that in a GM, you should use only Ac spark plugs. I used NGK. Is there any validity in sticking with AC Delco plugs?
The two injectors in the throttle body, is one specifically for the starting cycle? Or is it like the old 4 barrel carbs- one for light acceleration and the other for when you need more power?
i'm going to check the ground straps and such today. What part does that play in a vehicle running? I know that if it's not grounded good that the starter will not turn, but this spins good.

canucklehead

There is a primary injector, and a secondary/cold start injector.
How is your fuel pressure? Can you observe fuel spraying from the injectors in a fine spray, not dribbling when the engine is running? Have you ever had the fuel system cleaned?
If you pour a little raw gas in the top of the throttle body will it fire right up?

John M

This morning I could not get it started. I hadn't had it running since Tuesday. Spun and spun, no fires. Pumped it ten times and then it started firing, but wouldn't catch and run. Tries this about 10 times and then gave up.

I've had some suggestions made to me to check things so I took the doghouse off, and removed the air filter.

Turned the key on and hit the gas pedal to check for fuel flow. No fuel came from the injectors until I turned the engine over. Then there was a nice even pulsing spray. No dribbles at all. Inside of the throttle body was very clean and shiny. This time it started up. Like always, when it started up it ran great.

A friend had said that possibly the gasket between the throttle body and the manifold was bad. While the engine was running, I sprayed penetrating oil all round the base of the TBI and there was no change in the way the engine ran. In the past, with other vehicles, I've done this, and if there was a vacuum leak, the rpm of the engine would change. This didn't change at all.

My step son works with a mechanic and he mentioned a temp sensor. I did a parts check and the only one I could find that was vehicle specific for this was a coolant temp sensor. I haven't done any serious mechanics in years, but it seems to me that if the coolant sensor was bad, that there would be hard starting when the engine was warm?

I had also had it said that the fuel pump relay could be bad. Isn't this one of those things that is either bad or good? It's not an expensive part, but on other vehicles I have gone down the road of throwing a bunch of parts at it in the hopes of fixing the problem. I don't want to keep putting parts in this that aren't bad.

I appreciate the help on this, but I'm getting stumped.

canucklehead

So. Going back to codes. Handheld readers are hit and miss. You may just want to go to a shop and have it checked with a shop size tool... You never know. It could be as simple as a bad sensor somewhere.