One last shot... Breaking up!

[leadfoot]

Re: One last shot... Breaking up!

http://www.chevyhiperformance.com/techarticles/67498_hei_coils_modules/index.html

This is an interesting article which in a nutshell states that if you have an incompatible coil and ignition module, then it could affect performance.

Not sure what brand coil and ignition module you use, but if one is "high performance" and the other is stock, it could change the performance characteristics.

 

[BoostedSUV]

Re: One last shot... Breaking up!

http://www.chevyhiperformance.com/techarticles/67498_hei_coils_modules/index.html

This is an interesting article which in a nutshell states that if you have an incompatible coil and ignition module, then it could affect performance.

Not sure what brand coil and ignition module you use, but if one is "high performance" and the other is stock, it could change the performance characteristics.

I've been running an MSD coil since the truck was all stock, last year I updated to an MSD distributor and the truck ran fine for a while. When I started having this issue I went back to the stock coil, I swapped in an Accel ign mod, then went back to MSD coil.

 

[SloGN]

Re: One last shot... Breaking up!

i have a idea.


Wit the truck running probe the 12V side of the injectors. it may be that there is a low voltage issue there and it's causing a problem for the injectors to open under higher fuel pressures.


These trucks have very shitty wiring from the factory. Are the 50's low impedance?

 

[SloGN]

Re: One last shot... Breaking up!

I'm not positive but I'm pretty sure they're low impendance. I bought them from a member a few years back and all I remember is they are RPM flow matched 50lbers. I can certainly test the voltage to the injector and see what I have. I can probably just do it right at the harness right? Or should I check at each individual injector?

check at each injector you may have a bad wire going to a injector. The low impedance injectors draw more power. I know phil long had to hot wire his injectors and ecm due to simialir problems

 

[BoostedSUV]

Re: One last shot... Breaking up!

check at each injector you may have a bad wire going to a injector. The low impedance injectors draw more power. I know phil long had to hot wire his injectors and ecm due to simialir problems

That's a good thought I will check that tomorrow night... I did hot wire my ECM already but I will have to look into how to hot wire the injectors the same way. Thanks I will report back!

 

[WyoSyclone]

Re: One last shot... Breaking up!

That's a good thought I will check that tomorrow night... I did hot wire my ECM already but I will have to look into how to hot wire the injectors the same way. Thanks I will report back!

I think that 'hot wiring' the injectors, or the ECM, basically accomplishes the same thing... I broke my injectors out of the ECM supply at the firewall right by the dizzy.... stabilized my ECM voltage.... the injectors can take quite a bit of current to trip, especially at higher fuel pressures.... I can send a couple of pics of how I did mine.

 

[BoostedSUV]

Re: One last shot... Breaking up!

OK I promised to report back so here are my findings:

I have 13.53 volts at each injector, even when the truck starts breaking up. If I disconnect the fuel pump the truck shuts off immediately so I guess that means all the injectors aren't hung open, but I could have one or 2 bad ones.

I got my new sending unit assembly today, just waiting for the new Walbro pump from Racetronix. I am going to drop the tank and see if anything looks "off" in the mean time. I should be have it all back together early next week. Wont be around this weekend to mess with it.... I'm not convinced it's fuel pump but I will change it just for a piece of mind. It's cheap and easy enough,and my tank is already just about empty :tup:

 

[BoostedSUV]

Re: One last shot... Breaking up!

I pulled the tank out the truck tonight to change the pump and I noticed right away that the return line on the sending unit was twisted. I don't know if it was causing a problem but luckily I have new one. The second thing I notice was I did indeed have a Walbro knock-off pump in there and not a real one. So I'm please to know that I now have a true Walbro. The third thing I noticed and the one that bothers me the most is there was was no insulation left on the wires for the fuel pump. The were frayed all over the place and when I lifted it out some were actually touching each other!!!! Now I know gasoline is corrosive but shouldn't the wires for a submerged pump be "immune" to that? Check out the pics below.

Needless to say, I cleaned out the gas tank, installed a new genuine Walbro, and swapped out the sending unit. I will try to get the tank back up tomorrow but if not it will have to wait a week since I will be on vacation. What do you guys think of this??

 

[midnightbluS10]

Re: One last shot... Breaking up!

Holy crap, that's scary! There's now way that wasn't causing some kind of problem.

 

[SloGN]

Re: One last shot... Breaking up!

I pulled the tank out the truck tonight to change the pump and I noticed right away that the return line on the sending unit was twisted. I don't know if it was causing a problem but luckily I have new one. The second thing I notice was I did indeed have a Walbro knock-off pump in there and not a real one. So I'm please to know that I now have a true Walbro. The third thing I noticed and the one that bothers me the most is there was was no insulation left on the wires for the fuel pump. The were frayed all over the place and when I lifted it out some were actually touching each other!!!! Now I know gasoline is corrosive but shouldn't the wires for a submerged pump be "immune" to that? Check out the pics below.

Needless to say, I cleaned out the gas tank, installed a new genuine Walbro, and swapped out the sending unit. I will try to get the tank back up tomorrow but if not it will have to wait a week since I will be on vacation. What do you guys think of this??

That wire didn't corrode from the fuel. That damage came from too much current being used by the pump going south.

I think you need to upgrade the wring on the sending unit. and never use butt splices use solder and heat shrink tubing..

Is the ty gas tanks metal?

 

[fauXGT]

Re: One last shot... Breaking up!

Chinese made knockoff pump didn't have enough lead in the plastic jacket of the wires. Wasn't gasoline proof. :rotf:

 

[BoostedSUV]

Re: One last shot... Breaking up!

That wire didn't corrode from the fuel. That damage came from too much current being used by the pump going south.

I think you need to upgrade the wring on the sending unit. and never use butt splices use solder and heat shrink tubing..

Is the ty gas tanks metal?

It's a cheap newer metal tank I changed 3 years ago. I used to have problems blowing the ECM B fuse a while back (now I know why) so I upgraded all the fuel pump wiring with a Racetronix 10ga hot wire kit about a year ago. The funny thing is the sending unit wire was not affected, it was just the cheesy harness that came with the cheap pump. As far as the butt connectors, you're probably right I should have soldered and heat wrapped them. Fortunately the new Racetronix Walbro kit is "plug and play" and it just plugs right into the sending unit with a nice harness, so no soldering is necessary. :tup:


I don't think this will solve my problem but I'm glad I pulled the tank! This will solve a future problem!

 

[NJ93TY]

Re: One last shot... Breaking up!

Matt your truck is dangerous, I cant believe I rode in it before.

 

[BoostedSUV]

Re: One last shot... Breaking up!

Matt your truck is dangerous, I cant believe I rode in it before.

you loved it! lol

 

[SY2455]

Re: One last shot... Breaking up!

Matt it has been said about the current already, but if you look at that connector it is melted from the heat. You were driving a time bomb waiting to happen. I'm glad you found this before it went boom.

 

[BoostedSUV]

Re: One last shot... Breaking up!

Matt it has been said about the current already, but if you look at that connector it is melted from the heat. You were driving a time bomb waiting to happen. I'm glad you found this before it went boom.

That pump has always bothered me in the back of my mind, I'm glad I got it out and it's fixed now because I'm figuring if those 2 wires touched and sparked I could have had a real problem!

Now I have a new sending unit and wires, New walbro and harness, and I'm using the Racetronix 10ga hotwire kit. That should solve this from becoming a future issue. I'm definitely glad I stopped being lazy and dropped the tank because that was scary when I pulled it out and realized the potentials!

If there's any else I didn't do to prevent this let me know before I put the tank back in! :tup:

 

[WyoSyclone]

Re: One last shot... Breaking up!

Yup, remember the 747 that went down off the coast of NJ when the center fuel tank exploded from an internal spark? You were not too far from having that same thing happen... Yikes!

 

[SY2455]

Re: One last shot... Breaking up!

If there's any else I didn't do to prevent this let me know before I put the tank back in! :tup:

Make sure that the replacement fuel hose inside the gas tank is rated for fuel injection and E85. If it isn't, then it will fail in about 6 months. I have some so call hose from a fuel pump replacement that is mark for fuel injection but the rubber turn soft in the tank and look like a balloon when I found the problem in my daughter truck.

 

[SloGN]

Re: One last shot... Breaking up!

being that it's ametal tank you should add a ground to the tank itself. those kits usally comes with a little braided wire that clips to the edge of the tank and then to the frame.

 

[berzerker]

Re: One last shot... Breaking up!

gee ! bad fuel pump ring a bell !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!