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Car rolls smooth, but rough when gas applied?


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Hey guys

Going down the highway if I'm just coasting the car rolls really smooth. If I hit the gas to speed back up the car is rough. I can feel it in the steering wheel and it almost feels like the car is bouncing a little bit. It doesn't do it all the time but it started last night and it did it once today also.

I'm getting some creaking from the right front, and a popping noise sometimes. Both of my ball joints have been done recently. I had a guy help me with the passenger side ball joint and I think he messed up my tie rod. I inspected it and the boot on the tie rod is not secured. The metal band that secures the tie rod wasn't on tight enough apparently and the boot slipped out.

I also get this weird grinding sometimes. It mostly happens when I leave work, the parking lot exit is a decline. The noise happens when I'm going down the decline, braking, and turning the wheel to the right. When the grinding noise happens it also feels like there is some resistance as well. Like something is binding up.

Can a bad tie rod cause these problems? I'm not 100% with my terminology here and I'm going to go inspect it again and get some pictures so it's clear what I'm talking about.

Edited by lothos

WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn.

Cheers!

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The tie rod is the bar on the left with the boot in the back and the ball joint in the front, right? The boot in the picture is the one that is loose and not connected. The metal band towards the transmission is the one that came off.

WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn.

Cheers!

5% discount code at RockAuto.com - click here for your discount!

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The tie rod is the bar on the left with the boot in the back and the ball joint in the front, right?

Correct.

No, a tie rod should not cause the symptoms you describe. It simply "ties" the steering knuckle to the rack.

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No, a tie rod should not cause the symptoms you describe. It simply "ties" the steering knuckle to the rack.

Any ideas what's causing my issue? Or any tips on what to look for and check out?

I'll be doing that tie rod tomorrow, inside the boot is bone dry.

WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn.

Cheers!

5% discount code at RockAuto.com - click here for your discount!

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Got that tie rod replaced.

As far as the car shaking when I hit the gas, I think I have an engine miss.

I just did a tune up with ACDelco plugs and wires. Also replaced a bad coil pack a couple months ago with an Autozone coil.

WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn.

Cheers!

5% discount code at RockAuto.com - click here for your discount!

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Funny, I had read that a couple of times, and I was going to suggest miss and you concluded to that. Did you solve it yet?

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Funny, I had read that a couple of times, and I was going to suggest miss and you concluded to that. Did you solve it yet?

Didn't have much daylight left so I'm going to take a look at it after work tomorrow.

I'm not sure if the cheap autozone coil I used is the issue, or what the problem is.

Any suggestions for how to hunt this down would be appreciated.

WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn.

Cheers!

5% discount code at RockAuto.com - click here for your discount!

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Anything from AZ is always suspect.

Unless you counted threads and did not move the wheel when you replaced the tie rod, you'll need to realign it.

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Funny, I had read that a couple of times, and I was going to suggest miss and you concluded to that. Did you solve it yet?

Didn't have much daylight left so I'm going to take a look at it after work tomorrow.

I'm not sure if the cheap autozone coil I used is the issue, or what the problem is.

Any suggestions for how to hunt this down would be appreciated.

There is a power balance test you can do via the onboard computer. It disables each fuel injector one cylinder at a time. That should at least help you narrow down which cylinder is the problem, if any at all. When you disable the injector on a cylinder that is working properly, the RPM's should slightly decrease, and you should be able to notice a slight misfire. If a cylinder isn't working properly, there will be no change when the injector is disabled. You may have to cycle through the cylinders a few times to get a good reading.

Start the car, leave it in park.

Hold the OFF and WARMER buttons on the climate control until everything lights up and it enters diagnostic mode.

You can either wait for any codes to finish being displayed, or push the DOWN (or lower) button on the climate control to skip through the codes.

You should then see PCM? displayed. Push the UP button.

PCM DATA? will be the next thing to display. Hit the DOWN button until you see PCM OVERRIDE? on the DIC. Then push UP to select it.

Overrides display in the form of PS01 with the number changing to correspond with the system selected for override.

You can use the UP or DOWN button to scroll through the systems. You want PS04.

Once you see that, on the climate control digital display you will see 01 for cylinder 1. Pressing the WARMER button will cycle through the cylinders from 1-8. Starting with cylinder 1, hold the COOLER (blue) button down to disable the fuel injector. Releasing the button enables the injector again.

Do this for each cylinder and note if there is a change in RPM's or if there is a misfire. If there is no change at all, then that cylinder isn't working properly. That could be fuel related or spark related, but this should at least help you narrow it down to a cylinder (or 2 or 3).

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This sounds more like a driveline issue to me, an engine miss won't cause a grinding noise. I'll bet you have a half shaft that has gone bad.

Never underestimate the amount of a persons greed.

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Coil issues are very hard to find unless the coil has completely given out, even with the power balance check. Missing on light acceleration will not show up on this test, only a constant miss at idle can be found this way. Your best bet is to replace the coils, one at a time, with a known good one until the issue is resolved.

I am with JohnnyG on the half shaft. You also might be having problems with rust buildup on each edge of the where the pad contacts the rotor. This can cause a grinding sound as the edge of the pad cuts into the rust. A turn of the rotors to clean the rust off will cure that.

Let us know if you fix it.

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Coil issues are very hard to find unless the coil has completely given out, even with the power balance check. Missing on light acceleration will not show up on this test, only a constant miss at idle can be found this way. Your best bet is to replace the coils, one at a time, with a known good one until the issue is resolved.

I am with JohnnyG on the half shaft. You also might be having problems with rust buildup on each edge of the where the pad contacts the rotor. This can cause a grinding sound as the edge of the pad cuts into the rust. A turn of the rotors to clean the rust off will cure that.

Let us know if you fix it.

I did the power balance check and that's how I determined a coil was bad. It took 3 or 4 different times running the test to finally narrow it down, the rough idle wasn't very bad. It's still missing at idle now, very slightly, but acceleration is where it misses a lot.

I will order an ACDelco coil from RockAuto and swap it in, and see if that fixes it.

The engine miss and the grinding noise are 2 separate issues I think. I think I was confusing the grinding noise and the engine miss that just showed up as symptoms of the same problem.

I didn't know rust on rotors could cause a grinding noise. The photo of my rotor is an older picture, and they're worse now. I've replaced the back 2 rotors, but it's probably time to replace the front 2 as well, I don't think they're thick enough to turn.

The grinding noise typically happens when I'm driving forward, going down the decline exit of our parking lot, braking, and turning the wheel to the right. I imagine that's putting some weight down on the front end. I'm just not sure what could be under there making the noise. And I can't remember if the grinding noise happens if I don't apply the brakes, I will try to reproduce it tonight.

WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn.

Cheers!

5% discount code at RockAuto.com - click here for your discount!

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Surface rusted rotors will make noise, but only for a few stops until they get cleaned up.

I was not talking about surface rusted rotors, they will make a noise when the rotor is wore where the pad contacts the rotor and the edges of the rotor have rust build up on them compounding the "slight groove" cut in the rotor. Turning the rotors will smooth the surface and take out the rust buildup. It only takes a very slight surface grinding to smooth things out.

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The grinding noise typically happens when I'm driving forward, going down the decline exit of our parking lot, braking, and turning the wheel to the right. I imagine that's putting some weight down on the front end. I'm just not sure what could be under there making the noise. And I can't remember if the grinding noise happens if I don't apply the brakes, I will try to reproduce it tonight.

Well I haven't been able to reproduce the grinding noise since I started this thread. I quoted the description of when it typically happens in case that gives anyone some ideas.

The new coil is on order and should be here soon, but I'm on vacation next week and might not get it in time. I'll post again and keep everyone updated as soon as I can.

Thanks guys!

WARNING: I'm a total car newbie, don't be surprised if I ask a stupid question! Just trying to learn.

Cheers!

5% discount code at RockAuto.com - click here for your discount!

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The grinding noise typically happens when I'm driving forward, going down the decline exit of our parking lot, braking, and turning the wheel to the right. I imagine that's putting some weight down on the front end. I'm just not sure what could be under there making the noise. And I can't remember if the grinding noise happens if I don't apply the brakes, I will try to reproduce it tonight.

Well I haven't been able to reproduce the grinding noise since I started this thread. I quoted the description of when it typically happens in case that gives anyone some ideas.

The new coil is on order and should be here soon, but I'm on vacation next week and might not get it in time. I'll post again and keep everyone updated as soon as I can.

Thanks guys!

My rear rotor was grinding a few weeks ago and I knew the pads were o.k.. It all stopped when I put the car in reverse and a small pebble around the brake pad fell out.

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