vibration when car stops

[clarksober]

Hi all,
my 1987 fwd wagon vibrates when it's not moving, like at the traffic lights, in park.
I was told it might be the engine mount /motor mount, but I cannot find all the engine mounts, i ordered parts thru autozone and aap, they came in different size.
Could anybody here give me some directions about where they are (a picture will be helpful)? I have to eliminate the vibration before putting other new parts in it, thanks.

[ARCHINSTL]

Download the FSM for info on mounts.
The motor mounts are the same, whether 2WD or 4WD, sedan or wagon, MT or AT..
The transmission mounts for 2WD and 4WD may be different - not all parts sources make that distinction, unfortunately.
OE Toy transmission mount number is:
4WD MT Rear Transmission Mount OE part number: 12371-15070
Also visit viewtopic.php?f=7&t=2174&hilit=mounts

The AT and MT rear transmission mounts are different
Anchor brand for MT is 8377
Anchor brand for AT is 2685
Other AM manufacturers use similar numbers.
As noted above, 2WD MT/AT may be different than 4WD mounts; I do not know.

While this link to dlb's thread is about the 4WD shifter seal replacement, you can see the trans mount in the pix; it is just above the rusty spot on the exhaust pipe. Now as he notes, this is the view after removing the X-member to which it is bolted.
viewtopic.php?f=7&t=9701
Also view this link to dlb's thread - check the 6th photo in the series and you can see the X-member mentioned above: viewtopic.php?f=7&t=6388&hilit=seal
Tom M.

[Petros]

Hi Clark,

Welcome to the forum. There are several things that can cause a vibration, motor mounts is one of them. did the vibration just start, or was it there since you bought the car? How long have you had it? And where are you located?

Make sure to diagnose the problem BEFORE you try and fix it!!! Or you will waste time and money and get frustrated. As a guess I would say it is not likely it is bad engine mounts that is causing it. Could be, not not likely in my experience.

The two front engine mounts are on either side of the engine, one below the alternator/air conditioner, the other next to the power steering pump below the intake manifold. Both are over the lower cross member, you can see it from under the hood looking down in the engine compartment. These have to be noticeably bad if that is the cause.

The third one is at the rear cross member behind the transmission, you can see if from under the car about even with the back of the driver's/passenger's front seat. It is on the upper side of the rear cross member and holds up the aft end of the trans. it bridges across the center tunnel of the floor of the car.

The first thing I would check is to verify that the idle speed is high enough, that is an easy no cost adjustment on the carburetor. There is a screw along side the carb on the side where the throttle cable attaches to bellcrank on the end of the throttle shaft, just turn it in a turn or so and see what happens (it will not harm a thing if it idles a little too high).

If that does not solve it back it off and than I would look for a vacuum leak. Go read the FAQ sections on vacuum leaks. they are not hard to find and fix, it is just there are a lot of different vac lines to check. But this check of the vac system, and vac operated devices before you do anything else. If there is a vac leak, or a misrouted vacuum line, you have to correct that first or no other "fix" will work. It is possible there are several problems contributing to the vibration, if so you have to find all of the issues causing it and fix it or it will not run properly.

Let us know what you find and get back with us and we can tell you what to try next. We will help you narrow it down and guide you on how to fix it yourself. If who ever told you it was an engine mount is a mechanic, I would not bother going back to him. He might be well meaning, but the last place I would look would be the engine mounts, the toyota engines mounts are pretty durable and rarely need to be replaced, even on a 30 year old car.

good luck

[irowiki]

Auto or manual?

[clarksober]

Thanks guys.
I should add the details of my car at first. I recently bought it from FL for less rust. It's a 3A engine, auto, fwd, 210000mile. It vibrates before I drove it from fl to MD with potentially bad outer tie rod(LF) and driving shaft(LF, bad boot). It needs alignment since the right front tire was so bad I had to replace it to make the trip.
With your help, I think I found the 2 front mounts, I didn't look far back for the transmission mount, I will check it later.
The front 2 mounts are not very bad, but one of them is covered some old oil, although it is still in good shape, soft and not shattered.
I noticed after I pressed the gas pedal, it will vibrates less. Is it the idle speed? I don't have a tachometer to find out the correct idle speed, that's why I didn't do anything to the adjust screw, I will give it a turn to see the result.
I dont know much about vacuum leak, I checked YouTube for general method, but haven't try them, and I will check the posts here since they are more specific for the car.
I appreciate you guys help and please guide me through all the repairs, thanks.

[clarksober]

Some new things I noticed while I was driving it back.
It's not easy to get above 70mph, I noticed the throttle valve adjust cable is loose (gas pedal is loose too), and adjust the nuts behind the carburetor seems not help, need a new cable or it's different style of adjusting? Thanks.

[ARCHINSTL]

NOTE - SEE EDIT ABOVE FOR CORRECTIONS IN RED; I ERRED ON ORIGINAL POST.

Tom M.

[irowiki]

Hi, few things:

What do you mean by "not easy to go over 70", on flat ground, up hills? 70-75 MPH is about all you are going to see from this car, realistically, as it was designed to go 55 MPH. It only has three speeds and no overdrive! Once you tune it up (plugs, wires, cap, rotor) it should be a little better. My auto FWD wagon is happiest around 60-65 MPH.

If you are used to V6 engines, an I4 will vibrate a lot more due to the design of the engine. The auto also vibrates a lot more, especially when in gear and you have the brake on. Upping the idle will help some.

How loose is the throttle cable? It will be looser than say, a new car, in my experience.

[clarksober]

Thanks, Tom. I think I got the wrong part.

The vibration is not subtle, I have been drive 4 cylinder car for several years, and it's worse than that. on flat ground, it's hard to accelerate over 70, the speedometer has 110 on it, so I suppose it can do better. it got 33 while driving under 65.
The cable is about 1 inch loose.

[irowiki]

Newer I4's have balancer shafts, and are usually transverse, which also helps. A longitudinal I4 will vibrate by nature, the auto makes it far worse, especially if idle is set to factory default. I speak from owning two auto Tercel wagons. I have kicked up the idle while in neutral to around 1200 RPM on mine, which brings it down to around 900 when in gear, stopped.

The speedo going to 110 means nothing, earlier tercel models only had an 85 speedo and that was more accurate. Past 75 MPH you are doing about 4500 RPM and reaching the limit of your power, especially with a worn out engine. The auto transmissions on these cars were just not designed for high speed highway use.

Maybe post a picture of the slack, there should be some slack in it, I'll get you a comparison picture of mine later.

Here's some RPM to speed pictures for you (I swapped my cluster for a tach in my auto T4), this is the 4WD auto which is geared a little lower, but it'll be similar. My speedo was off by 3 MPH so it looks like I'm going faster in each one.

65

tercel auto 4wd 65 mph.jpg

70

tercel auto 4wd 70 mph.jpg

75

tercel auto 4wd 75 mph.jpg

80

tercel auto 4wd 80 mph.jpg

At 85 she was SCREAMING and I would not ever do that again!

[dlb]

agreed with irowiki. do not expect to get that car to 110 mph. remember that the engine only has 62 hp, and the auto trans on these cars make them even more gutless. i had one for a while and hated it because of that. if you want speed and power, you bought the wrong car.

[irowiki]

For science, on my way home, I was going 70 MPH on a fairly level stretch of road in my 87 FWD Auto (same car as the OP).

I gunned it, and she went from 70-75 in five seconds.

[lannvouivre]

Thanks, Tom. I think I got the wrong part.

The vibration is not subtle, I have been drive 4 cylinder cat for several years, and it's worse than that. on flat ground, it's hard to accelerate over 70, the speedometer has 110 on it, so I suppose it can do better. it got 33 while driving under 65.
The cable is about 1 inch loose.

My Vibe's cluster goes to 120 MPH, but it has a governed speed limiter at 110 MPH. Governed speed limiter as in the computer cuts fuel at 110 MPH, Toyota has it set up as such to prevent power/drivetrain damage. Well, the GT version is limited (it has the 180 HP engine, mine has 128 or so HP). I'm not 100% positive it's limited on my car, honestly, but going up to 110 MPH is hard even with double the horsepower of a Tercel and only 600 or so more pounds, not to mention more modern drivetrain and such.

[marlinh]

Just wondering if your car is actually running on 4 cylinders.

[Petros]

I drove an auto trans 4wd cross country twice, and as I recall 75 mph is about it on level hwy. low end acceleration is not bad (5 oto about 35 mph), but sluggish above there.

Try upping the idle speed, you will not harm anything even if you get it too high. do not worry about not having a tach, if it makes the vibration go away it will be fine. If it is too high what you will find it takes excessive brake pressure to hold it still in traffic or at a stop light when in gear. More of an annoyance than a safety issue. I once drove an auto trans car that would idle so high it would drive alone at about 18-20 mph if you left your foot off the brake. The TPS was bad (an EFI mazda), replacing it brought the idle back down. Your car does not have a Throttle Possision Sensor, that is on fuel injected cars only.

Easiest way to look for a vac leak, after you have looked over all of your vac lines to make sure they are connected and none are split or leaking, is to use a can of carb stray cleaner while the car is idling. squirt it around in short bursts at various places on the vac system and carb, from different angles and locations. If there is a leak the engine will change speed when you give it a squire where the leak is located. some brands, like Gum-Out, will speed it up, other brands will slow it down (they use different compounds). Either way, if the idle speed changes when you squirt it at one particular place, you located the leak. You can test the carb cleaner by giving it a short burst down the carb to see how it reacts to it.