Chevy & GMC Vans

Hello all, I have a 93 Astro, 4.3, it gave the previous owner fits and now it has been giving me fits too. The van normally starts and runs great but it will often die at an idle like at a stop light or a sudden stop or a drive thru (most embarrassing) and then it is very difficult to restart. When you try to restart it it turns over normal but acts like its not getting either fuel or fire. The previous owner had a new fuel pump installed but that did nothing to cure the problem. I can hear the pump engage when I turn the switch off and back on so I'm certain its working. If you keep your foot on the accelerator holding the rpms up there it will not die but man its wreaking havoc on the brake shoes. I have put approximately 3 to 4 thousand miles on it since I've had it, it doesn't splutter or miss, it pulls the mountains like a V-8, holds highway speeds great, gets good Mpg's, and seems to run all around great except for this dying issue, but its getting to the point I'm half afraid to drive it in town or heavy traffic because you generally block traffic for 5 minutes trying to get it started.
Its kind of weird but if I start it in morning and it idles smoothly for 5 to 10 minutes I usually have no trouble that day with it dying but if it idles for a moment and dies I will fight it dying all day. The only lights that ever come on in the dash are the anti lock lights and it is charging, carrying oil pressure, and running with in proper temps. I'm in the mind that it might be something electrical but honestly wouldn't know where to begin on a GM. Any suggestions?

Coils are a common problem.

Welcome to the site.

Could you please tell us if it is a TBI or "W" engine CPI.It's in the vin number.

When it acts up,could you check for spark at one of the spark plugs and if it has any or what color the spark is.

I would put money down that it is the spark control module in the bottom of the distributor. I had 3 of these act up and give me the exact same problems you are saying.

I'm with SmileSafari. Check the coil. After I replaced mine, no more hard starting problems.

Thanks guys for the quick responses and the welcome. I haven't been able to check for spark partly because I am usually alone and have no one to crank it for me and partly because if I have someone with me it will start while I'm under the hood almost as if its laughing at me. lol. I won't be able to mess with it the next couple days but I will get the info requested and also dive in to the spark issue. I was thinking about changing the module in the distributer but every one I ever had to go out they just quit and wouldn't restart. My buddy has a junk van I might be able to rob some parts off of to save some $$$ in diagnosis.

check your leads as well. When I had the stalling problems I also had bad leads and they would spark around on the reflective metal surface on the inside of the dog house. When we had the dog house off the van ran like a champ when we put it back on the van would backfire. Took a little while to find the cause.

Ok, I got a few minutes to tinker and here is what I have come up with so far. Its a fuel problem for sure because its getting fire and while cranking I sprayed fuel into the throttle body and it started up. Once running you can rev it up just fine, you can hold the engine at any speed with out interruption, but when you allow it to drop back to idle it may idle for 20 minutes or it may die quickly. Either way once it dies it takes a long time cranking it over to get it started again unless you spray fuel to it manually in which case it fires right up. You can hear the fuel pump engage and it was put in new recently thinking it was the culprit. I'm thinking it has to be the injectors or the pressure valve but I'm just guessing. I don't believe it to be a filter because it only effects low RPM's and at idle and in my experience the filter causes problems when more fuel is needed or at higher RPM's. Someone mentioned an throttle position sensor as a possibility but I haven't a clue if mine even has one or where it would be. Just haven't worked on this type vehicle before.

Ok strike that last post I didn't have any idea what the problem was. lol. I read on another post by "v8famvan" how to check the module and I performed that test and if I did it right it is the module. Guess if we'd layed money down "Kidhauler" would have won. lol. I couldn't find a "W" or a "TBI" in the vin number as 1Gary mentioned so I'm not sure what engine it is other than it is a 4.3. I will try to replace the module (it only has one) tomorrow or tuesday and see if that cures the problem, I think it will. Hoping anyway.

I used to grab them from the autowreckers. They are very expensive up here in Vancouver for some reason. I used to keep a spare one in the glove box on my 91 just incase.

I've had some of the same issue with the 4.3 in my Jimmy and after talking to our shop mechanic, he asked if I pushed down on the accelarator any at all while cranking and of course, me being a carb guy, I just can't break that habit. ANyway,,after keeping my foot off the pedal,,it cranks every time. I've spent as long as 20 minutes trying to crank it at times. What is this all about ??

Rebel wrote:I've had some of the same issue with the 4.3 in my Jimmy and after talking to our shop mechanic, he asked if I pushed down on the accelarator any at all while cranking and of course, me being a carb guy, I just can't break that habit. ANyway,,after keeping my foot off the pedal,,it cranks every time. I've spent as long as 20 minutes trying to crank it at times. What is this all about ??

Mine won't start unless I do push down on the accelerator pedal. Then I have to goose it once or twice to get it to keep idling.


Lumpy

hillbilly469 wrote:Ok strike that last post I didn't have any idea what the problem was. lol. I read on another post by "v8famvan" how to check the module and I performed that test and if I did it right it is the module. Guess if we'd layed money down "Kidhauler" would have won. lol. I couldn't find a "W" or a "TBI" in the vin number as 1Gary mentioned so I'm not sure what engine it is other than it is a 4.3. I will try to replace the module (it only has one) tomorrow or tuesday and see if that cures the problem, I think it will. Hoping anyway.

Glad to see that the test came in handy for you hillbilly469.

Well I did finally get to change out the module and the ole girl is running like a champ. I really appreciate all the help. v8famvan Thanks for the info on how to test that thing. I may have nickel and dimed it for a long time, never would have guessed that module would control injection.

I'm having this problem now,changed and checked everything.I got 60 psi fuel pressure and a bright blue nice spark.still won't start.Please help. She is a 94 CPI 4.3