Issue: The car bounces back and forth like there are no shocks on acceleration above 20 mph.
Basically, I will be accelerating and everything will be fine and dandy until I hit a bump or jerk the steering wheel back and forth quickly. Then the back of the car gets WAY out of line. It bounces back and forth so much that if I don't let off the accelerator I would lose control of the car. If I let off the accelerator, the car straightens itself back out after a bump or two. If I brake, the issue stops immediately (the harder I brake, the faster the bouncing stops).
This started when I went to lower the car. I had it on lowering springs, I took it to the alignment shop, drove it home and had this issue. I also replaced literally every part of the suspension.
What I replaced: - Struts in back twice, shocks in front twice, didn't fix it. I currently have coilovers on the rear, but going back to stock in the rear did NOT fix the issue. - Springs: I have tried lowering springs, stock springs, did not fix the isssue - The bushings in the rear are old poly ones, the front are new poly ones - All ball joints are brand new and from Rodney Dickman - Rear tie rod ends are brand new - I replaced all bolts(A-Arm, Cradle, and Strut tower bolts) with metric 10.9 and grade 8 bolts of the exact same size and length. I have tried going back to the stock bolts everywhere, didn't fix the issue.
Does anyone have any idea what could be causing this?
I know this may be a stupid question but are you sure the upper frame rails haven't rusted through? It seems like you covered all the bases with the suspension so I would look at the frame just for the hell of it. Here is a pic from someone in Canada who had issues. You need to remove the wheel well liner to see this part of the car. If this is the issue, unfortunately the car is finished.
You can see that when this occurs, the only thing holding the entire rear of the car together is the front cradle mounts.
[This message has been edited by IMSA GT (edited 08-01-2020).]
I know this may be a stupid question but are you sure the upper frame rails haven't rusted through? It seems like you covered all the bases with the suspension so I would look at the frame just for the hell of it. Here is a pic from someone in Canada who had issues. You need to remove the wheel well liner to see this part of the car. If this is the issue, unfortunately the car is finished.
So, they have certainly not rusted through, there is next to ZERO rust on the vehicle (it is from New Mexico and the body has like 50k miles).
The only way I could see those nut housings being loose is if they got over torqued and broke the welds, but I was able to get them as tight as ever when I checked just now.
When you say "bounce" is this up and down or does the car sway back and forth?
Honestly, its both. Or the up and down is so severe I can't tell. If I continue to accelerate and let it get worse and worse the front suspension bottoms out.
It is definitely not a "sway". I currently can't do more than 30 miles an hour because it is so bad.
I did shorten the front bump stops by about an inch. Could that have caused it? I have stronger springs in the front now, and I feel like because it only happens under acceleration the issue has to be in the back.
Edit: Nevermind, the issue existed before and after I shortened them.
[This message has been edited by Threedog (edited 08-01-2020).]
Not sure if you covered the rust issue or not but I guy in the local club had an issue like this and it was b/c his cradle was loose b/c of rust issues. All new parts and it could not hold an alignment. Front cradle was the issue. Car felt loose all the time. Even put in a new front cradle thinking it was bent or something but it was the space frame that was shot. He parted the car b/c it had a lot of great stuff on it and thru the frame away.
Not sure if you covered the rust issue or not but I guy in the local club had an issue like this and it was b/c his cradle was loose b/c of rust issues. All new parts and it could not hold an alignment. Front cradle was the issue. Car felt loose all the time. Even put in a new front cradle thinking it was bent or something but it was the space frame that was shot. He parted the car b/c it had a lot of great stuff on it and thru the frame away.
Rob
Yeah, everything is good in terms of rust, not a spot on it.
I did have the front cradle removed and powdercoated..but I have checked. All bolts are right, it was put together correctly. I am going to change the front inner and outer tie rod ends as well, to see if that fixes the issue. Maybe it is more back and forth than up and down?
You state this is a 3800 swap? And you have lowered it? This may may be an off the wall check, but check to make sure none of your cv joints are binding. Pay close attention to the inners. You could have took out one of the inner cup bearings when taking apart the suspension. Or one could be pushing in too far into the tripot. This will give a loping feel. And sometimes very violent. Recently replaced the center section on the right side. I had forgotten what I had used before and installed one that was about 1 inch too long. Every time the car loaded down the rear(over bump, acceleration, etc.) would have a violent vibration.
Did you have the car aligned after you installed the lowering springs? Check the torque on the big bolts that join the strut to the suspension upright. I've known alignment technicians not to torque those fully, which results in big handling problems when they slip
- First I am going to replace the front tie rods (inner and outer), as it might be a "side to side" thing. - Then I will have it aligned (even though the issue first showed up when the car was aligned) - Then I will check the CV axles. They are brand new, and were the same length as the old ones, but it is possible one isn't in all the way or there might have been a small difference in length(is it possible to over torque the axle nuts on the bearing side? I just made those tight instead of putting them to a specific torque).
When I took my front inner and outer tie rods ends off, I discovered this. Is it normal? (this is the passenger side of the steering rack, tie rod removed, the bolt I am pulling on is the outside steering damper bolt)
- First I am going to replace the front tie rods (inner and outer), as it might be a "side to side" thing. - Then I will have it aligned (even though the issue first showed up when the car was aligned) - Then I will check the CV axles. They are brand new, and were the same length as the old ones, but it is possible one isn't in all the way or there might have been a small difference in length(is it possible to over torque the axle nuts on the bearing side? I just made those tight instead of putting them to a specific torque).
When I took my front inner and outer tie rods ends off, I discovered this. Is it normal? (this is the passenger side of the steering rack, tie rod removed, the bolt I am pulling on is the outside steering damper bolt)
If it is not normal, could it be causing major issues? And should I be rebuilding or replacing my steering rack?
My opinion is that that is to much play. But that is not causing your rear end bouncing problem. How much play do you have in your steering wheel? Turn the steering wheel back and forth slowly to see how far it turns before you feel it statr to turn your front wheels. The play in that rack can cause some slop in the steering wheel or mushy feeling steering.
Did you replace the rear lower ball joints? They're hard to check for looseness without getting a pry bar in there and checking for play. My left rear lower ball joint was shot but seemed ok when tugging on the wheel up and down and side to side. When I took the control arm off to install poly bushings, I could see the ball joint was dry as a bone and ready to pull out of the socket! Was getting a MAJOR wiggle when doing any type of steering maneuver at highway speeds. Bad enough that I would need to slow down til it stopped. Verify that the cradle bolts are torqued properly and check ALL the suspension bolts for tightness including the rear tie rods.
------------------ 1984 Indy Fiero
[This message has been edited by ag9123 (edited 08-02-2020).]
I replaced all ball joints, and have checked every bolt.
The more questions I answer, the more I think about this..
Is it possible that an improper alignment has been the cause of all of this? It actually started after I got it aligned.
I rebuilt the whole suspension, drove it to the shop, then when I left the shop it started doing this. I can’t quite remember if it was doing this before I went to the shop (it was a short drive, and months ago)...but could they have caused this somehow? Even though the machine said the car was aligned?
Did you check all the nuts and bolts after the alignment? It's possible they left something loose...it happens. Hopefully they gave you a before and after printout of the alignment specs. Can you post those here if you have it?
I know from personal experience, if the rear toe is set wrong, you'll have a wild ride. This is especially true if the rear wheels are toed out. Every time you hit a water puddle or a bump or something, the rear end will step out.
Also, once an alignment shop forgot to tighten the bolts on one of the rear struts after setting the camber. It was like riding a bucking bronco! I got a free alignment out of that...
Thanks for the help guys! I went ahead and got a steering rack anyway, figured it couldn't hurt (I also didn't like the play in the current one, and it was the last mechanical part that was 30+ years old!). Gonna install this week and hopefully get it aligned by Friday, will report back.
I am pretty much at a loss, but I decided to check my (new) front upper ball joints as a friend mentioned that they are directional and I don't remember paying as much attention as I should have when I insstalled them a while back.
I got ACDelco 43D0026A ball joints of Amazon, but the same ones on rockauto refer to "additional camber adjustment". When I took the boot off, I noticed that the ball joint has a deep "groove" on one side. Should it look like this? Are they in there backwards?
[This message has been edited by Threedog (edited 08-11-2020).]
I am pretty much at a loss, but I decided to check my (new) front upper ball joints as a friend mentioned that they are directional and I don't remember paying as much attention as I should have when I insstalled them a while back.
I got ACDelco 43D0026A ball joints of Amazon, but the same ones on rockauto refer to "additional camber adjustment". When I took the boot off, I noticed that the ball joint has a deep "groove" on one side. Should it look like this? Are they in there backwards?
Sorry, I don't know if they are or can be installed wrong, left for right. But if the alignment shop got it in spec, that could not be your problem. The ball stud should be able to swivel enough to allow the A arm to travel its full range of motion without binding. For example if the ball joints are directional, they might have more travel towards the wheel side of the A arm. This will allow for suspension droop without binding. BTW, that looks like a clean job you've done.
I literally my replaced everything that can be replaced.
This ball joints thing is the last thing I can try.
Thats cool, I understood. I was just agreeing that it was the right thing to do. My confusion is that you said you hoped that the ball joints were binding? I asked if that was a typo? Either way, if the ball joints did bind up, I don't think it would cause your problem. My guess is a loose part somewhere? Did you add a sway bar to the rear or change the front?
Not a guarantee, but worth mentioning. I had my Fiero driving nice, then replaced a few components, lowered it and put on another set of wheels. Suddenly it drove horrible, like it had a mind of its own. I thought it just needed an alignment. Didn't help. Went back multiple times, replaced every suspension component, raised it back up. Nothing helped. Decided to throw my old wheels back on it in a last ditch effort. Drove perfect. Did some testing and found it was the front tires on that other set. Replaced those and all has been well. So, all that to say, have you checked the tires? Any abnormal wear? Or possibly a bent wheel? I learned the expensive and frustrating way that tires and wheels can negatively alter your handling tremendously if something isn't right.
Edit to add: Perhaps something as simple as the wheel balancing is off and causes an up and down bouncing. Also any loose or worn bearings? Jack the car up with the wheel on and give the wheels a shake. Any play? I think someone already mentioned the axles. Its worth checking. I had a friend who's mr2 had the cvs put together incorrectly not allowing it to make up or down motion. The car felt like it was driving on rocks and eventually busted the cv.
[This message has been edited by liv4God (edited 08-12-2020).]
I'm with cmechmann on this. I believe the driver side is supposed to be a stock fiero manual axle. But the passenger side is made up of a variety of parts and the length is not stock Fiero length. You said you installed new axles the same as the originals. I'm assuming the new axles were the same as came with the original engine and transmission, before the swap. I have a 3800 sc swap, but I did not do the install, so can't tell you the correct procedure for the passenger axle length. Likely it would be found in the search function on here. I have not experienced myself, but have read several threads with issues related to loose bolts on the rear struts after an alignment, as well.
I'm with cmechmann on this. I believe the driver side is supposed to be a stock fiero manual axle. But the passenger side is made up of a variety of parts and the length is not stock Fiero length. You said you installed new axles the same as the originals. I'm assuming the new axles were the same as came with the original engine and transmission, before the swap. I have a 3800 sc swap, but I did not do the install, so can't tell you the correct procedure for the passenger axle length. Likely it would be found in the search function on here. I have not experienced myself, but have read several threads with issues related to loose bolts on the rear struts after an alignment, as well.
Ill check these out as well. I did have the same axles in before and after the suspension rebuild (both with the 3800SC), so I doubt that is it (but it might be).
I want to play devils advocate here and ask, did you physically remove the rear wheel well liners and inspect the upper frame rails and cradle mounting points or are you just assuming they are good due to cars history? Just trying to eliminate the obvious. Before you throw any more parts at it, i would inspect the frame and cradle for rust or even cracks if you haven't already.
As far as the axles go i'm fairly sure that the drivers side is a stock Fiero axle, while the passengers side is a combination of manual Fiero and automatic donor parts. Many builds on here and YouTube. I'm not sure you can even get a stock axle to fit but if you did, that might be the problem.
i would also try a different set or rims/tires. Even if you borrow a set from somebody for a test drive.
[This message has been edited by DLCLK87GT (edited 08-13-2020).]
You may want to try jacking up one end at a time and spin the tires, I had a high speed shake(doing freeway speeds , 50 up to 80) in my 65 chevelle, never figured it out until I let it idle in 2nd gear on Jack stands. The right rear had a bulge about 3/8 inch tall that wrapped around 30% of the tire. I was on a long road trip, did 80-90 several times, that started on the last 2 days. SCARY!
[This message has been edited by Franked (edited 08-13-2020).]
- the new coil overs I got from the Fiero guru - the stock springs and new struts - the lowered springs and new struts - the stock springs and old struts (that previously worked) - the lowered springs and old struts (that previously worked)
What. The. ****.
[This message has been edited by Threedog (edited 08-15-2020).]
Wow, that's really bad!! It's like the motor or cradle is just slopping around but hard to tell from that angle. I'd like to see a video from the sides aimed at the rear wheels to see what's moving.
Edit to add, after watching that vid a few times it's hard to see but it sure looks like your rear tires are actually turning in and out.
Again I'd check the frame, cradle even the trans and engine mounts.
[This message has been edited by DLCLK87GT (edited 08-15-2020).]
