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Help! 90 lx 5.0 aod bucking and chugging like mad

1725 Views 4 Replies 2 Participants Last post by  145566
Hi new here... I have a 90 lx with the aod and 302. When cruising with steady throttle and under low rpms it will chug and buck so hard it will darn near break your neck. If you floor it and drive it like ya stole it it will smooth out and run well. I'm not sure if it's coming from the tranny or the engine. I took it to the shop this past weekend and when they drove it it didn't act up for them so they didn't do anything for me so I took it back after a few days. I had a bad brake booster so I got that fixed and I thought maybe that that was causing the bucking and chugging but it didn't. It's back to running way rough again. Man, why couldn't it have been running bad when at the shop.. ANyways please help, I've been researching and researching and I'm pretty much at a stand still. At first I thought it was torque converter, so I bought one, didn't have it put it because I was told that it wasn't the tc although the mech didnt check he just drove it and said no not that. Anyways help please
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Hi 90lxwhite! For the bucking and chugging at low speed, its probably because you forgot to, or the last owner forgot to change the pcv valve during their last tune up or within 30, 000 miles. Mine was doing the same thing and i was experiencing some power loss. Change the pcv valve and check the vacuum tubes (they should be worn out by now) and that should fix the problem. It stopped the bucking for my car! GOod LUCK!
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Ok thanks I'll try that. When you changed the pcv did you put in a new screen that's under it?

Will the comp throw a code if the check engine light isn't on?
What do you mean new screen? the pcv valve is like 6.99 at o reileys. as for throwing codes, the check engine light doesnt have to be on to throw codes
my cel was not on when i was throwing codes 41, 91 (being lean) and 33 which is the egr not functioning.

The CEL is only on now since i think the EGR has really gone out (its not dirty) and i need to replace it.
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There is a screen under the pcv. I hear that it can get clogged and cause probs
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