Big CLUNK...

[Ed]

Ok, so here's my first post on this site. So I guess I'll just say Hi to all on the site. I don't know much about mechanics and repairs but I do know that big CLUNKS are bad.

I own a 85 tercel 4wd wagon, standard transmission. I've owned it for the past 3 months now and this is the first time i've noticed something like this. It feels like the car pops out of gear if I accelerate fairly quickly, but sometimes it occurs under normal driving as well. It can occur in any gear. It happens really quickly and drives normal afterwards. Also, it seems to occur more often at lower rpms. Also, it seems to occur more frequenlty if the car isn't warmed up yet.

The clunk is like this: the gas is on under normal acceleration, and for a moment the car stops accelerating as if i cut the gas, and a split second later the gas is on again and it jolts me forward because my foot is already half way down on the accelerator.

Thats pretty much the best I can describe it. I'm not sure if it is transmission related, or if it has to do with motor/tranny mounts. I don't know about the oil thats in the tranny or if replacing it would fix it?

I tried searching for other's who've had the same problem but I didn't find much. I've never experienced this with any other car, so it could be a normal sign of a dying transmission. I don't know. But I don't have much $$ to spend on this thing although it runs very well except for this thing. It's only been a couple days now since it first happened. So I'm hoping its revivable.

I'm going to a local shop in Langley, B.C. to see if they can help. But any info any of your fellow terc owners have I'd love to hear it.

[Mattel]

I had this sort of thing happen once.. If it's not poping out of gear it could be
a Clogged fuel filter perhaps? (here's hoping) Especially if you've run low on juice lately. I had a clunk which was the engine and tranny going from on to off (fuel/no fuel) at highway speeds and clunking on it's mounts like a high speed roll start

should be along the fuel line into the carby and is a real easy replacement part.

unless it's something else?

Good luck

[Ed]

Mattel...that might just be it.

I drove to Mister Transmission today and told them exactly what was going on. They said that it doesn't sound like it is transmission related, rather, it seemed to them that it was engine related. Because it does seem to stay in gear but the gas isn't consistantly getting to the engine.

Another note: Starting the car takes a couple minutes of pumping the gas then holding it at above 2000 rpms. If I don't then it will just die. So maybe the problems holding an idle from a cold start will also point towards a fuel line related problem.

[Ed]

I bought and installed a new fuel filter, and it seemed to cure the problem completely after a short test drive. However, the next day I experienced the same acceleration problems i was having before without improvement, so I decided to take a look and inspect all those hoses and connections.

The tube connected to the Choke opener was kinked, and I fixed that problem, took it for a drive, and again, seems like the acceleration problems fixed...sort of.

I still have that fuel/no fuel hesitation, but now usually not enough to cause a clunk - mainly poor acceleration. Another thing, last night as I was driving it home the Gas pedal was sticky! I could only press it about half way, and if i took my foot off it stayed accelerating unless i pried it loose. But when I got home and did some more test driving on harder accelerations and such, the gas pedal didnt ever stick, but i did notice a hesitation at half throtle when i gun it.

So i'm not sure what that means but I'm reading the manual like crazy to analyze each system thats involved.

Any input would be great...especially about the sticky gas pedal...i have no idea what that could be from.

[Typrus]

That is odd... It went away by itself? Look to see if something jammed up inside of it. Stray hose?

I'm getting much the same thing. MASSIVE hesitation under acceleration. I have to gun it hard to get away from a light. It happened right after I tried moving my dizzy hoses from one ported vacuum source to another, so I might blame that. If that fixes it for me, then I might urge you try the same? Vacuum issues, distributor advance/retard in particular?

[ARCHINSTL]

RE: The gas pedal stickiness.
I had a similar problem, as have others. I removed the cable & casing from its anchorage at the carb, elevated it and allowed a thin lube (I used White Lightning, left over from the bike shop) to drip through until it exited inside the cab (protect the rug). The difference was striking.
Also check the smoothness of the throttle linkage/clean with carb spray. Also check the tension on the throttle return spring. Make sure there is just tiny bit of slack on the accel cable. There is a threaded adjuster you will notice.
Aforementioned helped quite a bit - but I ultimately replaced the carb for other reasons.
Tom M.

[Typrus]

Swapping the vac lines back fixed it up for me.

My clutch cable probably needs that... Stupid thing binds and pops periodically...

[Petros]

Once you lube the throttle cable I would check two things.

1. check that all the vacume lines are conected, and none are cracked/leaking (you can spray carb cleaner on the hoses w/ the engine running to look for leaks, listen for change in engine speed). Also check that all carb linkages are connected and working properly.

2. The other thing is the carb might have crap floating around inside of it. I had this and it made it run like yours. I simply took off the top cover of the carb w/o removing it from the engine. Be careful there are a lot of tiny parts that could get lost. I cleaned out the carb with carb cleaner spray, removed the check balls, and accelerator pump and cleaned out all the passages, and put it back together with new accelerator pump (old one was shot). It ran great afterwards.

Good luck,

Peter

[keith]

Peter, you live dangerously. I used to do carburetor repairs on vehicles, but never one of these. I recommend removing the carb, and taking it apart in a large tray or bowl.

[Ed]

Well the problem has been isolated to the carb. I sprayed some carb cleaner in it and there was an immidiate improvement, as prior to using the cleaner the car was running extremely rough. After using carb cleaner...no/minimal hesitation.

There's a carb for sale from a parts car in my area, and the guy wants 60 bucks for it. He said it ran fine when the car was working. I'm thinking of getting it and giving it a cleaning then installing it. Would this be just the same as cleaning my current carb out? I'd check it out first before purchasing it, but i'm afraid i dont know what to look for at all.

I think I'll buy it, clean it, and keep my old one for parts (any that are good), if I can even do that.

Last week I didnt know what a carb was...this is one of those times where you feel WAY over your head.



p.s. the gas pedal hasnt sticked at all since and it seems fine now...weired, but i'll probably lube up the cable anyway.

Thanks for all the imput so far.

[waynehoc]

Ed, be sure any carb you buy is from a MANUAL trans wagon, as they are a different animal from the carb on an auto trans wagon, with (some) different 'supporting' emission devices.

The Canadian manual trans wagons DO NOT have an O2 sensor and the carbs are non-feedback carbs. The Canadian auto trans wagons have an O2 sensor and are feedback carbs. I'd be willing to bet the manual and auto trans carbs are jetted differently as well.

Wayne

[Ed]

Ed, be sure any carb you buy is from a MANUAL trans wagon, as they are a different animal from the carb on an auto trans wagon, with (some) different 'supporting' emission devices.

Must the carb be from a manual transmission wagon as well, or can it be from the hatchback? My impression is that if its a carb for a 3a engine it'd be the one i need. But I'll double check if it is from a mt or an at.

[Typrus]

Not looking into a Weber at all? Or are they allowed up in BC?

[Ed]

Not looking into a Weber at all? Or are they allowed up in BC?

Yeah I've read all about the Webber. And I've put some thought into it. But It's tough justifying spending over $300 on a car I bought for a grand. Also, I'm only using the car for winter, in summer I ride a motorbike and the 4runner is going to be on the road too.

[Ed]

Not looking into a Weber at all? Or are they allowed up in BC?

Yeah I've read all about the Webber. And I've put some thought into it. But It's tough justifying spending over $300 on a car I bought for a grand. Also, I'm only using the car for winter, in summer I ride a motorbike and the 4runner is going to be on the road too.