Interesting question about my van

[DreadHeadDrifter]

Hello everyone, this forums has been such a success at helping me fix a few small things on my van so far, and I must say thank you to everyone for your help and support. That being said, I had something interesting happen yesterday.

Before I traded for my van, a 1992 chevy G20 conversion van, the owner said he was trying to sell it but during the test drive it just randomly turned off. After I traded I replaced the radiator, the ignition coil, the distributor, spark plugs and wires, did an oil change and a fuel treatment. For nearly 2 thousand miles she has run perfectly. Yesterday in traffic while going maybe 5 mph, she just turned off on me, the check engine light came on. After that it immediately started back up with no problems and drove fine.

Now, I thought I had fixed this problem, but I guess not! I am starting to think it may be something electrical? Does anyone have experience with this or know what it may be? It is a 5.7 V8 engine, and runs perfectly. Just hit 113,000 miles. I am kinda of confused because after sinking a little money into this I thought I had fixed the issue, and can't seem to figure out what it is! Any thoughts or advice would be greatly appreciated. Thanks!

 

[wagoneer]

I believe that motor has EFI or electric fuel injection. Sounds like a loose electrical connection, go for the easiest first remove the filtration system and feel all the connections looking for loose
ones. My last GMC van was a diesel so not much help from me.

 

[LoupGarou]

A buddy of mine had a motorcycle that did that, it ended being the ignition switch. He doesn't have 10lbs of keys hanging off his keychain anymore.

Start the vehicle and try to wiggle the key in the ignition switch and see if it dies.

http://www.marketplace.org/topics/business/post-gm-recall-how-heavy-your-key-chain

 

[WheelEstate USA]

Had something like this happen on our Dodge twice in one day. Couldn't find anything wrong.
Changed the fuel filter and haven't had the problem since...that was months ago.

 

[Optimistic Paranoid]

Intermittent problems are a cast-iron bitch to diagnose.

92 should have had OBD1, I think.  Anything on the codes?

Regards
John

 

[NYboy]

My first post here, Hello all.
I don't know if this pertains to a G20 or not but this is a rather common problem with Astro vans and it sounds typical. Behind the battery on an Astro the is a wire loom that has a connection with a male and female coupler, these get hot and loose connection causing shut downs and other assorted problems. May or may not be your problem but worth a check.

 

[LeeRevell]

My '05 Grand Caravan did that to me once, as I was braking hard and entering a turn lane at an intersection.  Luckily no one behind me, and it restarted immediately.  Shouldn't be a fuel issue on an injected engine, so maybe electrical/ignition system?

 

[highdesertranger]

Paranoid said it, check your codes let us now what codes come back. btw, if you have multiple codes write down the codes in the order they appear. the proper way to fix codes is to fix the first one first then reset the computer and drive, the reason for this is one problem could cause multiple codes. do not go down the list and fix the easiest code first, that's how you end up spending a ton of money replacing parts that are not bad. lets I know, I have a couple of ideas but I want to hear what codes come back. highdesertranger

 

[29chico]

I suggest that you do the free stuff first.   Clean both ends of both your battery cables or replace them if they don't look good and solid.  Please remember to disconnect the negative cable first and then reconnect it to the battery last when performing this task. 

Your rig has throttle body fuel injection, with fuel injected vehicles that have some years on them I recommend the following:  

While the battery is disconnected, disconnect and inspect all of the sensor connectors where they attach to the sensors on the engine, if you see any corrosion clean them up.  If they look good push them on and off carefully a few times.  Do this to the low voltage wires that connect to the distributor also. Do the same with every relay that you can find, especially the fuel pump relay.

Good chance that doing the above will alleviate your ghost in the machine issues. 

If you really want to have a bunch less electrical issues in the future I strongly suggest the following:

Get a six inch long ground buss bar from a circuit breaker panel from an electrical supply house.  Then pick out a sheet metal location under the hood to mount it.  Sand the mounting location and the mounting side of the buss bar and then clean off the sanding debris.  Mount the buss bar with screws using liberal amounts of copper anti-seize on the screws and the sheet metal to buss bar interface.  Next connect at least a 10 gauge wire from the negative battery terminal to the buss bar.  Then use at least a 12g wire to your alternator case from the buss bar.  Then go a bit nuts with 14g wire to whatever ground points that you can think of.  Make sure to find the ground point for the engine computer and extra ground that also.  Find the main ground point for the dash instrument cluster and snake an extra wire there also.  Use crimp on loop style wire terminals wherever possible at the far ends of the extra ground wires from the buss bar.

What I have described above is called ground reinforcement.  It does not cost much or take very long to do.  It can prevent a whole lot of problems down the road on an aging fuel injected vehicle.  It can also help out really old vehicles that don't have computer controls.

 

[DreadHeadDrifter]

Okay sorry it took so long I have an update, I was waiting till it happened again before I post more, and it did. 4 times yesterday on my way home. I figured out the problem, kind of silly!

Sooooo after 4 engine cut offs on my way home I found out that...... my gas gauge sticks? It fluctuates A LOT after it gets to the half a tank mark, it showed I had a quarter tank of gas, but anytime I would go down a hill, with the fuel shifting towards the front of the vehicle, the engine would cut off, and the needle would almost be on empty. After filling my tank up, it ran perfectly fine, and now I understand why it took so long for this issue to happen again, I had to be almost out of gas!

So this brings me to my next quetion/project, is this something I can fix? Do I need to fix my fuel sensor in the gas tank? I think this model uses a floating type of sensor? Or should I just do the easy fix and always keep the needle at over half a tank so I never have to deal with the problem again.

Glad it isnt something more serious, kinda mad that my engine had to run out of fuel a few times for me to realize this issue, hopefully no damage was done. Thanks for everyones advice!!

 

[B and C]

I try to run off the top part of the tank.  When it gets to 1/2 on the gauge I start looking for a place to fill it.  I know I can still drive quite a ways though and sometimes plan that in (another 100 miles and there is cheap gas) and if it gets down to a 1/4 tank, I treat it like I am going to run out very soon and stop at the nearest gas although I could drive a lot further.  The fuel pump in the tank requires the fuel to be there to cool it.  It is never wise to continuously run it below 1/4 tank for this reason, because it causes the pump to overheat and wear out sooner.  It costs very little more to haul that full tank around that it does one that is always under a half tank and replacing that pump in the tank is not cheap and could leave you stranded somewhere.

Brian

 

[Almost There]

I try to run off the top part of the tank.  When it gets to 1/2 on the gauge I start looking for a place to fill it.  I know I can still drive quite a ways though and sometimes plan that in (another 100 miles and there is cheap gas) and if it gets down to a 1/4 tank, I treat it like I am going to run out very soon and stop at the nearest gas although I could drive a lot further.  The fuel pump in the tank requires the fuel to be there to cool it.  It is never wise to continuously run it below 1/4 tank for this reason, because it causes the pump to overheat and wear out sooner.  It costs very little more to haul that full tank around that it does one that is always under a half tank and replacing that pump in the tank is not cheap and could leave you stranded somewhere.

Brian

^^ This - and in a van that's over 20 years old there's probably several gallons of gunk in the bottom of the gas tank that you don't want to be sucking up in to the fuel lines.

If you know how many miles you get to a gallon and how big the tank is, it's easy to keep track of your mileage and start looking for gas at the 75% range. I used my 2nd trip odometer for well over a year on one of my vehicles that had the fuel gauge fail.
 
Dropping the tank to replace a fuel pump and/or gauge is a nasty and big job. I had to have it done once on the Astro because the pump failed - IIRC it was a $750.00 US job.

 

[NickTheoBennett]

So this brings me to my next quetion/project, is this something I can fix? 

I am of zero help with mechanical issues, but the car I had before I got my van had a similar problem.  I just used the trip meter on the odometer and reset it every time I fill up. 

10 gallon tank at 32 MPG meant I could go around 320 miles, so I just ignore the gas gauge and focus on the mileage.

 

[Gary68]

sure you can fix it,with a basic wrench and socket set you can repair 90% of your vehicle,but first you need to find out if it's the sending unit or the gauge in your dash,most likely the sending unit but it's worth the check,and before you go dropping the tank check for an access panel above the tank,they are as rare but do exist

 

[ramblingvanman]

sure you can fix it,with a basic wrench and socket set you can repair 90% of your vehicle,but first you need to find out if it's the sending unit or the gauge in your dash,most likely the sending unit but it's worth the check,and before you go dropping the tank check for an access panel above the tank,they are as rare but do exist

Agreed. It is more likely to be the sending unit IMO. If you do end up dropping the tank, consider making an access panel in case you ever have to do it again.

 

[Optimistic Paranoid]

If you do decide to drop it (and personally, I'd just use the tripmeter cause I'm lazy) then you should certainly drain all the old gas and flush the old tank to get rid of all the junk in the bottom.  Dispose of the old gas, or maybe filter it with a chamois if you must, and fill with fresh gas.

Regards
John

 

[highdesertranger]

well I tend to believe that the problem is just more than the sending unit being inaccurate. it sounds like there is a problem in the pump or pick up sock/tube or perhaps the baffle has come loose. I abhor in the tank fuel pumps. highdesertranger

 

[wagoneer]

Pull the tank clean the tank and understand problem, you will be so happy to realize this is not a non-re-occuring issue. just gives you power over the machine, good luck. I have a wax build-up in the diesel we all share the same....l.l.