Idles fine but stalls when put in gear!!

[Iheartmy85gmc]

Help please! I’ve been dealing with this problem for too long... my 305 starts right up and idles fine. But once I put her in gear and give a little throttle she dies down, cuts out, and stalls. I can keep it from stalling by giving it a little gas at a time and then letting off when it starts cutting out. Once it starts rolling I can stomp on it and it seems to “get past” the stalling point then she starts going great guns! This only happens when the engine is warming up for the first few minutes of driving then it seems to go away. I’ve replaced so many things I can’t seem to find the issue. Any input would be such appreciated! Thank you

 

[Honky Kong jr]

Help please! I’ve been dealing with this problem for too long... my 305 starts right up and idles fine. But once I put her in gear and give a little throttle she dies down, cuts out, and stalls. I can keep it from stalling by giving it a little gas at a time and then letting off when it starts cutting out. Once it starts rolling I can stomp on it and it seems to “get past” the stalling point then she starts going great guns! This only happens when the engine is warming up for the first few minutes of driving then it seems to go away. I’ve replaced so many things I can’t seem to find the issue. Any input would be such appreciated! Thank you

Vacuum leak? Converter locked?

 

[MrMarty51]

Accelerator pump is bad.
Remove air filter cover, look down the bores, open throttle, should see fuel spray into the front bores of carb.

 

[Dougnsalem]

Vacuum leak? Converter locked?

That advice from you? I'd put a BBC in it. Then you'll have enough power, that you wont die when you put it in gear and take off....


Lol .Jk

 

[Big Chip]

I would put it neutral, redline it and slam it into gear. Now this is the important part so pay very close attention: leave some room between you and the car in front of you. Beat of luck, BC out.


Sent from my iPhone using Tapatalk

 

[Iheartmy85gmc]

Accelerator pump is bad.
Remove air filter cover, look down the bores, open throttle, should see fuel spray into the front bores of carb.

Thank you! Accelerator pump is kinda what I thought, it’s just that I put a brand spanken new Carb on her! Just doesn’t make sense to me:/ I’ll open up the air cleaner and see if fuel sprays into the front bores though.

 

[Iheartmy85gmc]

Correction... it was a rebuilt one I bought off eBay. But it sure looked new! Lol

 

[1987 GMC Jimmy]

Rebuilt Quadrajet? I trust a mom and pop outfit with recommendations to do it, which there are some of them doing business on eBay. I don’t trust someone in Monterrey or Tijuana doing it on a larger scale for Edelbrock or Summit so I’d be careful with that. The acc. pump diaphragm, TCC solenoid, and vacuum leaks are all the suggestions I would have ran with, but something else worth looking at is your curb idle mixture. If that’s too lean, it’ll bog like crazy right off idle but perform well cruising and at off idle WOT. Anywhere outside of takeoff really. The fact that it idles fine, though, says to me that if it’s too lean, it’s not by very much so if you decide to make adjustments, I wouldn’t do so liberally.

 

[Snoots]

Rebuilt Quadrajet? I trust a mom and pop outfit with recommendations to do it, which there are some of them doing business on eBay. I don’t trust someone in Monterrey or Tijuana doing it on a larger scale for Edelbrock or Summit so I’d be careful with that. The acc. pump diaphragm, TCC solenoid, and vacuum leaks are all the suggestions I would have ran with, but something else worth looking at is your curb idle mixture. If that’s too lean, it’ll bog like crazy right off idle but perform well cruising and at off idle WOT. Anywhere outside of takeoff really. The fact that it idles fine, though, says to me that if it’s too lean, it’s not by very much so if you decide to make adjustments, I wouldn’t do so liberally.

X2

 

[Iheartmy85gmc]

Rebuilt Quadrajet? I trust a mom and pop outfit with recommendations to do it, which there are some of them doing business on eBay. I don’t trust someone in Monterrey or Tijuana doing it on a larger scale for Edelbrock or Summit so I’d be careful with that. The acc. pump diaphragm, TCC solenoid, and vacuum leaks are all the suggestions I would have ran with, but something else worth looking at is your curb idle mixture. If that’s too lean, it’ll bog like crazy right off idle but perform well cruising and at off idle WOT. Anywhere outside of takeoff really. The fact that it idles fine, though, says to me that if it’s too lean, it’s not by very much so if you decide to make adjustments, I wouldn’t do so liberally.

I’m gonna risk asking a stupid question and ask if my truck has no ECU, would I even have a tcc solenoid?? My truck is an 85 non computer and the tranny is turbo 350. If it has a tcc solenoid where would I find it?

 

[1987 GMC Jimmy]

Not a stupid question. Yeah, pre-ECM vehicles used a vacuum circuit to control lock up. The lockup switch should be on the firewall. TH350s got lockup in 1980, and 700R4s started that way in 1982. The solenoid itself is in the transmission visible when you remove the pan. The kind of failure with those that creates symptoms is being stuck locked where the vehicle will stall when you slow down to a certain point. I’m sure it could work the other way where you’ll have some resistance getting started, but if it’s not unlocking, it should be acting weird when you slow down, too. They can also stick unlocked where the transmission will run sloppier and hotter like if the lockup wasn’t being powered at all, but I imagine this is a bigger problem with a 700R4. Of all the suggestions, though, this one would be the least of my concerns.

 

[Iheartmy85gmc]

Thanks a million! Yea sounds like it’s not the problem I’m experiencing. I’m gonna check that darn accelerator pump for sure.

 

[1987 GMC Jimmy]

Also check that curb idle mixture. Mine likes 3.5-4 turns out from full lean, which is okay for a newer Quadrajet. I’ve heard of 7 turns even being the norm for some, but that seems pretty excessive to me. The old ones, as I understand, require around 1.5 turns out give or take a little. With mine, if you tried to do that, it would bog and stall big time on takeoff.

 

[Iheartmy85gmc]

Also check that curb idle mixture. Mine likes 3.5-4 turns out from full lean, which is okay for a newer Quadrajet. I’ve heard of 7 turns even being the norm for some, but that seems pretty excessive to me. The old ones, as I understand, require around 1.5 turns out give or take a little. With mine, if you tried to do that, it would bog and stall big time on takeoff.

Yea that’s what I’m gotta check right now, I didn’t see any extra fluid squirting into the primary’s from the accel pump when I gave it gas today so I’m thinking that’s working fine. Plus it revs up perfect when not in gear. It’s only when I put it in gear and give it a little gas that it stalls

 

[Iheartmy85gmc]

Curb idle screws adjusted! Used my timing light to see the rpm and also hooked up a vacuum guage too. The sweet spot ended up being just about 4.5 turns on both sides. This was a little farther out than was originally set so hopefully that helps my issue! Also checked my vacuum and it went from about 17” to 19” once I made the adjustments. God willing that’s it!