carbie auto bogging out when put into gear...

[htchbck]

Ok, this is on my sister's '88 carbie that I converted to auto (trans from a '97 Aspire) a couple of years ago. All of a sudden its developed this thing where it just bogs till it dies unless you feather the throttle when you put it in gear. Other than that it still runs/drives great, and idles fairly smoothly. We tried bumping the idle all the way up to 2k, but as soon as you put it in gear it drops to barely 500 and usually dies. Same when coming to a stop. You have to feather the gas to keep it alive. I've already tried messing with the timing, but nothing seems to help. Nice smooth idle, runs well going down the road, just dies when its in gear and not moving. My only though I have left is that the '97 Aspire is supposed to have a lockup torque converter... maybe it is locking up all most of the way all the time? Any guesses on how to check/fix that?

[Zanzer]

If you bump the idle up to 2k wouldn't that prematurely lock up the torque converter and make it want to bog when you put it in gear? Just thinking out loud here.

How does it do when driving down the road and you get on the gas? Does it act normally under a load or do you still have to feather the throttle? Just wondering if it could be fuel pressure related.

[crazyrog17]

Could the vacuum modulator have busted the diaphragm and be letting in air?

[htchbck]

Trans shifts normally during driving so I don't think the problem is with the modulator. Mark, you could be right about the lockup, I don't really know how they work on these, I'm used to a solenoid I can just unplug, or not lockup at all. But even when the idle is set at 850 (which is where it had been since I put in that trans) it does the same thing. But going down the road, its just fine, drives normally, just have to rev it when you are stopping. Or you can drop it in neutral. Then its fine till you put it back in gear.

[Team Lightning]

It almost sounds like the stall speed has lowered. Maybe you are right in that it's not completely unlocked.

[bhazard]

Maybe the converter sat for a long time and the clutch is seized up?

[FestYboy]

time to clean out the carb... there's a fuel restriction in the low speed circuit, or you have a vac leak.

[htchbck]

Brad, don't know how long the trans sat in the junkyard, but it has done fine for the last couple of years until this month. Hasn't sat for more than 2 or 3 days at a time since my sister got it.

Arty, I'll clean the carb out this afternoon and see if that helps, the main reason I was suspecting either the trans or timing is that it runs, idles and revs fine until it is put under a load, and even then once you get it moving it does great until you stop again.

[Zanzer]

Did the 97 Aspire have a computer controlled transmission since it was OBDII?

[htchbck]

Nope. Only wires going to it were the reverse switch, the park/neutral switch, and the kickdown solenoid.

[Movin]

The idle adjuster screw only uses about 1/3 of the fuel available through the idle jet. This jet if plugged is fairly easy to clean, pull the idle screw, energize the fuel shut-off and blow / flush debris back to the float bowl , then clean the bowl. If the secondary idle circuit is plugged, this one is harder to clean as you have to get air pressure or carb cleaner pressure lined up with the little holes where idle fuel comes out. On the secondary there is no idle screw to make cleaning easier.

This same debris is like dust but while cleaning things, clean the accelerator pump passages as well, especially where the check balls are, this same dusty stuff can cause intermittent weak shots because the balls don't always seal properly with this crud that collects there.

What is happening is you are getting plenty of fuel with high vacuum and no load, but when you reverse these conditions by dropping into gear you do not have enough fuel . A old chrysler 3.0 fuel injection fuel filter for a caravan or? will filter a lot finer and prevent this , only problem is they will fit the hoses but not the mount.