tbi issues, on my 88 gmt400

[Jims86]

jim, I was considering unhooking the trans mod line and plugging it, thinking it may have an effect, I'll have to try the booster line and see what happens.

ok, I added some stuff to that last post...racking my brain...you have been through absolutely every ******* inch of the system. Can you check that trans modulator for a leak?

 

[89Suburban]

And the wire harness, didn't you re-route that? Anywhere it can be rubbing open or something?

 

[Jims86]

Or even check behind the dash for vac leaks from the HVAC system. Wish I had a private plane to run around and help peeps fix they ****....Yo?

 

[Jims86]

And Jay, I have another to add to your list.
The ECM senses voltage, and when voltage goes low(dont know what the parameter is), even if ALDL says 12 or more, check all the Hot leads to the ecm, as well as the hot lead between the battery, and the charge post of the alternator....if it has one. If not, you know what to do, if you have not done it already. Also, I dunno if it was all in my head, but when I did the big 3 mod, I also, ran a large gauge wire between the ECM ground by the thermostat, to a bolt near the fuel pump cavity, and then to battery ground, and it seemed like it ran even better. Shure turned over faster.

 

[89Suburban]

And Jay, I have another to add to your list.
The ECM senses voltage, and when voltage goes low(dont know what the parameter is), even if ALDL says 12 or more, check all the Hot leads to the ecm, as well as the hot lead between the battery, and the charge post of the alternator....if it has one. If not, you know what to do, if you have not done it already. Also, I dunno if it was all in my head, but when I did the big 3 mod, I also, ran a large gauge wire between the ECM ground by the thermostat, to a bolt near the fuel pump cavity, and then to battery ground, and it seemed like it ran even better. Shure turned over faster.

For some reason the fusible link at the starter keeps coming to my mind. Trying to think of the heat related thing.

 

[RetroC10Sport]

I'll check them, the ALDL does say 13.4-13.8 even with the A/C and headlights on. It turns over quick but does take about 15-20 seconds to start when cold. When it's warm it starts with just a flick of the key.

 

[MrMarty51]

Or even check behind the dash for vac leaks from the HVAC system. Wish I had a private LEAR JET to run around and help peeps fix they ****....Yo?

Hey, I got You into something a bit faster, a aeeeroplane would never be able to keep up wit all of this.

 

[Jims86]

I'll check them, the ALDL does say 13.4-13.8 even with the A/C and headlights on. It turns over quick but does take about 15-20 seconds to start when cold. When it's warm it starts with just a flick of the key.

And the relay is priming for 2 seconds like its supposed to? What are the BLMs while warming up....123 or so?

 

[Jims86]

Hey, I got You into something a bit faster, a aeeeroplane would never be able to keep up wit all of this.

Yeah, that would be cool...I flew a Lear 25 in flight school. I just like to put along though. An old T-28 trojan, or A-1 Sky Raider come to mind.

 

[Swims350]

found a loose ground wire, no change. tried pawpaws computer afterwards and his map and still nothing.

It's started to develope a miss now too a kinda shake to it at idle and just off like it's missing.

going to find another set of plug wires and try em or just check all my plugs and wires.

 

[Swims350]

yea tried the booster line plugged no change.

 

[Jims86]

found a loose ground wire, no change. tried pawpaws computer afterwards and his map and still nothing.

It's started to develope a miss now too a kinda shake to it at idle and just off like it's missing.

going to find another set of plug wires and try em or just check all my plugs and wires.

Irritating, and it usually ends up being something right in front of our face.

 

[MrMarty51]

Yeah, that would be cool...I flew a Lear 25 in flight school. I just like to put along though. An old T-28 trojan, or A-1 Sky Raider come to mind.

I always figured a Flying Jenny biplane`d be good, stay low,slow and follow the roads.

 

[MrMarty51]

found a loose ground wire, no change. tried pawpaws computer afterwards and his map and still nothing.

It's started to develope a miss now too a kinda shake to it at idle and just off like it's missing.

going to find another set of plug wires and try em or just check all my plugs and wires.

You did`nt try a full tuneup before ??? That should be furst on duh list.

 

[Swims350]

not when it's all new stuff and only a few years old now.

especially not when it ran fine, rebuild the tb and it runs aweful.

I got accel wires on it and ac delco plugs, they've been on it for about 4 years now I think.