84 se bogs when accelerating (Page 1/2)
katie80 JUL 30, 10:58 AM
my 84 4 spd 2.5l does a weird thing when I accelerate. in first gear, the engine chugs hard for a bit then revs up as high as it should based on where the pedal is and I accelerate like normal. in second, it does the same thing, sometimes when it does this it feels like the engine stalled (lurching and whatnot). it does the same weird rev thing in third and fourth but it's just a hesitation in those gears. the fuel injector and fuel pressure regulator are new and it has a new fuel filter on it. what could it be? it didn't do this before (like a month ago.)

edit: it was the pump. I should've known since the pressure dropped when being revved with no load, even if it was only a little. the problem is completely fixed.

[This message has been edited by katie80 (edited 08-04-2021).]

katie80 JUL 30, 11:16 AM
I'd also like to add this is not a constant thing. it seems to be only when it is up to operating temp, after like 10 minutes of driving.
Xenoblast JUL 30, 11:24 AM

quote
Originally posted by katie80:

I'd also like to add this is not a constant thing. it seems to be only when it is up to operating temp, after like 10 minutes of driving.



Its most likely a spark issue. check your timing, and then give the distributer a refresh (new o-rings, new ICM, new pickup coil, new spindle thing and new cap). Also only use ac delco.

I had a lot of chugging on my car, and the problem ended up being that my massive exhaust leak on the headers made the afr wrong, so its worth checking if you have an exhaust leak.

[This message has been edited by Xenoblast (edited 07-30-2021).]

katie80 JUL 30, 12:06 PM
I'd like to add again. I took it on the highway and it was ok til like 60 mph and wouldn't go any higher, it actually slowed the car to like 50 mph. the check engine light came on and it was bogging bad. I got off the highway and it would not accelerate anywhere past 1/4 throttle. the check engine light was not on anymore when I got home so I couldn't check it. thoughts?
Patrick JUL 30, 12:20 PM
Your latest post sounds like a plugged cat. However, the other symptoms mentioned earlier might've contributed to its demise.

So in other words, make sure the engine is running properly before a new cat is installed (if the old one is indeed plugged).

[This message has been edited by Patrick (edited 07-30-2021).]

Rodrv6 JUL 31, 09:27 AM

quote
Originally posted by katie80:

I'd like to add again. I took it on the highway and it was ok til like 60 mph and wouldn't go any higher, it actually slowed the car to like 50 mph. the check engine light came on and it was bogging bad. I got off the highway and it would not accelerate anywhere past 1/4 throttle. the check engine light was not on anymore when I got home so I couldn't check it. thoughts?


Unless you've disconnected the battery, any codes that turned on the Check Engine light will still be in the memory of the ECM and can be retrieved easily.

------------------
Rod Schneider, Ball Ground, Ga.
"You can't have too many toys!"
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katie80 AUG 01, 09:45 PM

quote
Originally posted by Rodrv6:

Unless you've disconnected the battery, any codes that turned on the Check Engine light will still be in the memory of the ECM and can be retrieved easily.





I didn't even think about that. code 44. the internet has me thinking bad fuel pump. it bogs under hard acceleration and at high revs so I imagine it'd be a fuel pressure issue from the pump. I've had 3 fuel pressure regulators (the original, a replacement in the new fuel meter I bought because I screwed up the original, and the replacement.) the car sat from 2005 til I bought it earlier this year. probably super varnished. never checked it out. worst part is I have a full tank of gas right now. I'll just pump it into my other car using the pump.
katie80 AUG 01, 09:47 PM

quote
Originally posted by Patrick:

Your latest post sounds like a plugged cat. However, the other symptoms mentioned earlier might've contributed to its demise.

So in other words, make sure the engine is running properly before a new cat is installed (if the old one is indeed plugged).




what would cause a clogged cat anyway? I know it's been blown out since I bought the car. I'm thinking fuel pump since I have a lean fuel code and it sat in bad gas for a long time.
Patrick AUG 01, 10:38 PM

quote
Originally posted by katie80:

what would cause a clogged cat anyway?



If for example, an engine is misfiring and/or running rich, the cat innards can melt/disintegrate/breakup and plug the cat's exit pipe.


quote
Originally posted by katie80:

I'm thinking fuel pump since I have a lean fuel code and it sat in bad gas for a long time.



Although it's not as simple to test as with the 2.8, it would tell you a lot to know what the fuel pressure actually is.

I've had "bogging" issues with my '84 in the past. Here is a thread documenting my experiences.
katie80 AUG 01, 11:38 PM

quote
Originally posted by Patrick:

Although it's not as simple to test as with the 2.8, it would tell you a lot to know what the fuel pressure actually is.

I've had "bogging" issues with my '84 in the past. Here is a thread documenting my experiences.



since it's a lean fuel condition, I imagine there's a problem in the fuel tank. the engine doesnt like to be revved high at all or rev up fast. if it was an ignition or a timing issue I would imagine the issue would be different. I would be surprised if the fuel pump is still good and that hose in your posts fell off or something. I think the pump is original. I'm gonna try to drop the tank tomorrow, I'll just drain the tank using the pump into my other car. shouldn't be too hard, right? (I should've bought a car with less rust...)