'88 TBI 350 - multiple personalities

[brendo613]

Andy - TBI 350's may share the blue collar plight: wouldn't we all like a little more timing? Ar ar ar ar.

Martin - congrats on your post count collection! Lol. Fuel pressure buildup is a good theory for why the wait-then-crank method works.

Jim - since the high idle problem occurs at seemingly random cold starts, I doubt it's a vacuum leak issue. I do have new intake manifold gaskets for it, too ... eh, "lazy" me

Van's away for state inspection right now, but IIRC, there's a solenoid controlling EVAP flow. It's mounted on the same bracket as the MAP.

 

[brendo613]

Baby passed, yaaay. Taking it downtown tonight because I'm a little kid who wants to cruise around in a V8 rumble.

Anyone know a source for new weather stripping? Power windows are both dead, which I attribute to leaky quarter window seals wetting & shorting out the motors. Plus they whistle at 40+ mph and are VERY ANNOYING

 

[Jims86]

Andy - TBI 350's may share the blue collar plight: wouldn't we all like a little more timing? Ar ar ar ar.

Martin - congrats on your post count collection! Lol. Fuel pressure buildup is a good theory for why the wait-then-crank method works.

Jim - since the high idle problem occurs at seemingly random cold starts, I doubt it's a vacuum leak issue. I do have new intake manifold gaskets for it, too ... eh, "lazy" me

Van's away for state inspection right now, but IIRC, there's a solenoid controlling EVAP flow. It's mounted on the same bracket as the MAP.

That's the EGR solenoid.

 

[Jims86]

Baby passed, yaaay. Taking it downtown tonight because I'm a little kid who wants to cruise around in a V8 rumble.

Anyone know a source for new weather stripping? Power windows are both dead, which I attribute to leaky quarter window seals wetting & shorting out the motors. Plus they whistle at 40+ mph and are VERY ANNOYING

Wohoo! Seals will be a bit tough for a Van. Maybe compare the windo openings with a square P/U?

 

[brendo613]

Gotcha Jim.
Took the van downtown, ~20mi each way. On the way down, its old problems resurfaced. They sure seem like trans woes, but unless it involves lockup, it can't be. Symptom is slamming into second, and late shifts into every gear. Approximate shift times: 2nd gear 20-25mph, 3rd gear 35-40mph, 4th 55-60mph. As you can see, THIS WON'T DO. This erratic problem has got to go. FWIW, I pressed the brake at various points while accelerating through the gears; lockup disengages in 3rd & 4th as designed.

There's no very high idle present. If it's high, it's only by a few hundred RPMs. I'm perplexed how, if it's an engine management issue, it can seem like a transmission issue. Where do I begin? At your mercies, squarebody friends. TPS? EGR? Little green gremlins?

 

[Jims86]

Gotcha Jim.
Took the van downtown, ~20mi each way. On the way down, its old problems resurfaced. They sure seem like trans woes, but unless it involves lockup, it can't be. Symptom is slamming into second, and late shifts into every gear. Approximate shift times: 2nd gear 20-25mph, 3rd gear 35-40mph, 4th 55-60mph. As you can see, THIS WON'T DO. This erratic problem has got to go. FWIW, I pressed the brake at various points while accelerating through the gears; lockup disengages in 3rd & 4th as designed.

There's no very high idle present. If it's high, it's only by a few hundred RPMs. I'm perplexed how, if it's an engine management issue, it can seem like a transmission issue. Where do I begin? At your mercies, squarebody friends. TPS? EGR? Little green gremlins?

The only trans item thats ecm controlled is the torque converter clutch solenoid. the shift points are the Govs. job.
4th should come in a little before 40.
I would pull the gov out and clean it. its behind the large bearing cap on the drvers side rear of the trans. After the cap is off, it pulls out...have a catch pan ready for a tiny bit of fluid.

 

[brendo613]

This is a new, rebuilt trans though, and the erratic behavior comes and goes - just like before the trans swap. How could this be? There's no way 2 700R4's have the same oddball defect. I'd sell parts of my body on the black market if it is so!

 

[brendo613]

TPS checks out fine when hard shifting happens. The engine races and slams into gear far too late when the problem is present, which is not always. What could cause this intermittent behavior? I think something makes the van idle too high, but only sometimes. Problem disappeared during today's diagnosis.

 

[Jims86]

TPS checks out fine when hard shifting happens. The engine races and slams into gear far too late when the problem is present, which is not always. What could cause this intermittent behavior? I think something makes the van idle too high, but only sometimes. Problem disappeared during today's diagnosis.

I would start going through the wiring harness, and see if anything is chaffing. That is the only intermittent possibility. All other problems are either there or not. A vac leak:Leaking or not, not every now and then. Know whatta mean, Vern!. LOL!

 

[brendo613]

Guess I'll start tomorrow. What a bear! Odd how the problem comes and goes for a few days' stay. It's like some sort of perveted pest ...

thanks for the tip. The van did have mice at one point before. Maybe they had a nibble on the ol' harness.

 

[bucket]

Your current troubles do indeed sound similar to when I had 700R4 gov troubles.

 

[brendo613]

Found a second ground on the back of the 2-4-6-8 cyl head; guessing the harness has 2 grounds - one here & one @ the thermostat. I no longer think the problem is electrical. Can't find the ECM, btw ... where the hell is it? Anyway, if I hold the TV cable out more than @ its resting point, the big slam from park into drive presents itself. I bet I have a sticky TV valve. The cable seems to operate fine. When I depress the D-shaped tab to set TV length, it doesn't push in very far - is this normal? It would be really weird if my old trans & my new one had sticky TV valves. More likely it's the cable, but who knows.

 

[brendo613]

Cable removed, lubed up; ATF topped up (a little above full, oh well.) Taking the trip to NY in it tomorrow. TCC lockup switch makes bad contact unless pushed hard into housing. I'll keep an ear out for it disappearing tomorrow. Hope I don't get late, race-y shifting with 1000 lbs of friends & music gear in it

Hoping to finish heater core swap in the AM. Didn't do a very good job today of getting it out ... d'oh. Liftoff @ 2:00 tomorrow, hehe.

 

[89Suburban]

Good luck on the trip. Did you look under the drivers seat for the ECM. I got to look in the manual and see where it is when I get a chance.

 

[HotRodPC]

Baby passed, yaaay. Taking it downtown tonight because I'm a little kid who wants to cruise around in a V8 rumble.

Congrats. And you got some edumuhcation along the journey.