85 chugging sound
Thread Starter
Racer
Joined: Oct 2013
Posts: 483
Likes: 19
From: las vegas nv
85 chugging sound
so found a smog pump at junk yard off an 85, replaced that and a used egr solenoid, reset tps, was running good then it after about a 40 minute ride sounded liked a chugging train fromunder the car, idles noce but while in gear it has the for lack of a better term chugging sound and the idle gets a bit funky, but in par or netural it is hardly noticeable, could it be the egr> cat? sound like under the car, tapped the cat dont hear anything rattle, replaced the injectors last year , so i am at a loss anybody maybe O2 sensor?
Racer
Joined: Oct 2009
Posts: 433
Likes: 55
From: The Beautiful Pacific Northwest
Thread Starter
Racer
Joined: Oct 2013
Posts: 483
Likes: 19
From: las vegas nv
its starts up nice, once i go to drive it doesnt sound like a exhaust leak, when driving it sounds like...a deep cha cha cha , and goes faster and slower as i press the gas while driving, can slightly hear it in park but the idle get a tad jumpy
Racer
Joined: Oct 2009
Posts: 433
Likes: 55
From: The Beautiful Pacific Northwest
Is it throwing a check engine light? Any previous codes?
I would make certain it doesn't have any vacuum leaks, make sure the PCV valve is not sticking, reset the base idle, set the IAC, and reset the TPS.
Beyond that, I would look at the fuel pressure to make sure it is consistent, and if you haven't changed the O2 sensor and don't know when it was replaced last, go ahead and replace it. They are cheap and it wouldn't hurt to do it just to get it out of the equation.
Jared
Racer
Joined: Oct 2009
Posts: 433
Likes: 55
From: The Beautiful Pacific Northwest
Does anyone else hear what I hear?
I know we went through this about a month ago with that guy that bought that rattling Vette.
It's hard to judge what's making that noise, I do know what it sounds like to me. But, I also had a 77 GMC Eleganza that had a bad muffler and it would oil can with the exhaust pulses, and it sounded a lot like a knock.
Jared
I know we went through this about a month ago with that guy that bought that rattling Vette.
It's hard to judge what's making that noise, I do know what it sounds like to me. But, I also had a 77 GMC Eleganza that had a bad muffler and it would oil can with the exhaust pulses, and it sounded a lot like a knock.
Jared
Last edited by lotsofspareparts; Oct 9, 2019 at 09:51 PM.
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Racer
Joined: Oct 2009
Posts: 433
Likes: 55
From: The Beautiful Pacific Northwest
Your opening post doesn't mention having done anything with the ignition wires, but the noise sounds similar to what getting the firing order mixed up sounds like.
The speed of the sound is too slow to be crank-shaft speed. It's camshaft speed, which is what firing order is.
Another check is a vacuum gauge. If the needle drops with the sound (single cyl miss), I'd pull the valve covers and check the valve gear.
The speed of the sound is too slow to be crank-shaft speed. It's camshaft speed, which is what firing order is.
Another check is a vacuum gauge. If the needle drops with the sound (single cyl miss), I'd pull the valve covers and check the valve gear.
Sounds very strange and repetitive. It's there every revolution.
Jared
Thread Starter
Racer
Joined: Oct 2013
Posts: 483
Likes: 19
From: las vegas nv
Yeah I replace the wires about a thousand miles at best new distributor cap so that was all new but I found a wire leaning up against the valve cover so that might have sparked it the plugs are bad as old as the wires and I'll try and get a better video but I'm doing it by myself I have to get my old lady to get in and put in drive and hold the brake for me but I did replace the EGR valve and that ticking sound you hear is the smog pump I got it a junkyard for $16 so I just don't know I'm scratching my head my butt my cheek and that's pretty hard to do with two hands
Racer
Joined: Oct 2009
Posts: 433
Likes: 55
From: The Beautiful Pacific Northwest
Racer
Joined: Oct 2009
Posts: 433
Likes: 55
From: The Beautiful Pacific Northwest
I noticed the idle wasn't a consistent speed either, going from 600 up to 750 and back down again. My 88 does that when the A/C is on, or when I have it set to defrost. Compressor kicks on and off.
Jared