1st Gen Neon, worrying engine noise...

[RoadWarrior222]

Hi folks,

Been driving around my sister in law's Neon, I keep forgetting what year it is, 98 or 99. At low RPM under load, like trying to accelerate when it's in 3rd gear (auto) at 25mph say, or go uphill at city speeds, I'm hearing a very light..."t-t-t-t-t-t-t-t" can't hear it much better with the window down.

If it was a bit louder I think I'd probably be able to tell light spark knock from injector noise, from headgasket leak, but as faint as it is at the moment, I'm not having much luck. Could be small manifold or exhaust gasket leak too I guess, or could be some ticky lifters even.

Any special suspects I should check for? What corner/side the HGs tend to go? Find Neons a bit annoying for engine access, so don't know if I'll actually see anything on it when running (Plus it's hard to load the motor by yourself and look under the hood at the same time.)

She had "unexplained" low coolant a couple of times a few months ago in warmer weather. The place she took it to "tightened a hose clamp" and said it was fine. I am not sure if that is moron code for "buggered if we know" or they really did find a connection that was spraying.

Thoughts?

RW222

[Turbodave]

Leaking exhaust gaskets and cracked manifolds are not uncommon, so I would start there. May have to remove the airbox and heatshields to get a look.

[Aries_Turbo]

hmmm. my wife has a 98 dohc atx neon and it makes all kinds of good noises when its cold. warm, its pretty quiet. hers has 190k on it though. hers does ping but its not a real consistent pattern. more random.

a buddy of mine makes ticking noises when hot and its baffling the crap out of him. it was silent after he replaced the lifters (SOHC) but its doing it again after it gets good and hot.

Brian

[RoadWarrior222]

I won't worry if I get to hear it well enough to tell it's lifter tick. Unless I hear it over 3000 or so RPM.

Still can't get a handle on the "shape" of the sound if you like, whether it's tappy, or chuffy, or hollow, really annoying. I'll have to see if I can get it to do it while, brake torquing with the hood up. Might hear it better... damn NVH sound padding... Might have to get creative with small funnels and lengths of tubing to listen to different corners of the motor while I brake torque.

I would try recording devices, but low frequency sounds really don't seem to come out too well. I tried capturing an odd knock I had in my Voyager, really couldn't hear it on the recording. That was a strange one, thought it was rod knock, then thought it HAD to be a broken flexplate, then when I got the tranny off it turned out it was the transmission oil pump contacting the back of the clutch pack because the bushings/washers were worn paper thin. And because that was all bolted inline with the crank it transmitted right along it, and sounded loud under the oil pan. That noise was louder than this one too.

[RoadWarrior222]

To busy to get a proper look yet. However another thing worrying me now is that it runs rough, 3 cylindery but not totally missing on startup after cooling down from fully warm. I'm kinda wondering if the thermostat is buggered because it takes a while to get fully warm, and I've mostly been doing short drive in it. However, when it has been fully warm, it runs rough next start from cold. So kinda thinking there might be a little coolant getting in one cylinder as it sits, compression/combustion pressure keeping it out for now. But I guess I should see bubbling in the coolant, will have to check that.

It had a "rough when starting" issue a while back too, where she got sold new plugs, wires, and an injector clean, which smoothed it slightly, but she wasn't all that happy.

She was mentioning coolant bubbling into the overflow and worrying it was overheating, that was when she got the clamp tightened and it appeared okay but the weather went cold. I'm guessing that could have been combustion pressure in the cooling system making trouble....

Also driving around when it starts the slight t-t-t-t it seems a little chuggy, and it sounds more like it's coming from the passenger side. Still can't hear the noise well enough but it's sounding more "chuffy" than tappy.

What's the likelihood of head warping on these if the HG is buggered? I mean, what's the chances of success with just cleaning things up and sticking an updated HG in without getting the head skimmed? Not that I'll be wanting to tackle this, just know she won't have $1000 for a *cough* professional in this area to do it.