Hi all.

New here, but have read information from other posts. Thanks for that.

I have an '03 SXT that is my "kids car" and bought it from an auction dealer. Car was a disaster first with electrical issues...wouldn't start after it was driven and got hot...was a bad computer and that was finally fixed after many guesses and repairs.

Lately I've been bothered by the "clunking" especially at low speed. I had already replaced the struts all the way around but the clunk was still there...low speed and potholes. I didn't think it was suspension related, so I filmed the engine with the hood up and revving it and going into forward/reverse. Motor lifted right out of the compartment and dropped...at least 3 to 4 inches of up and down. Motor mounts shot!

Ordered new motor mounts online. Did the passenger top and bottom (haven't got to the tough middle mount on that side yet) and did the transmission mount on the driver's side. Lots of work on that one but got it done and all three of those were toast...especially the passsenger upper and lower. They were completely broken free.

After replacing the transmission mount, I took it for a test drive. Clunking was much less....still there...UGH....but less.

BUT....my brakes were awful. Mushy brakes...scary....no quick stop even when trying to stomp on the brakes.

Couldn't for the life of me figure it out. Didn't touch the brake system. Only removed the front wheels for the job and had the car on stands. Checked the brake lines....no problem. No leaks. No loose or missing vacuum hoses.

My mechanic friend told me it was most likely a master cylinder. Ordered that and replaced it. Replaced all the dirty brake fluid, too. Bench bled the cylinder, then bled the whole system. Should be good to go.....test drive said otherwise. Still mushy brakes and no ability to come to an immediate stop, even from 10 mph.

Read everything I could about this issue and kept coming back to the brake booster. Checked all the vac lines and the check valve on the vacuum "T" fitting on the brake booster. All good.

BUT....then I accidentally pulled the HVAC vacuum line (small diameter line that goes through firewall above heater core stubs) right out of the firewall. HOLY CRAP. I am SO not a mechanic. Now what? Had no ability to change from outside air to inside air.

Went back online and found a post from a Neon owner who replaced the heater core. He had step by step pics and I could clearly see where the vac hose should go. I was able to peel back gasket at heater core stubs under the hood and see the female vac fitting and re-insert the small line....one problem solved!

BUT...brakes still mush. So, checked all the vac lines there, replaced the check valve "T" and the grommet. No change. Replaced vac line from the T to the engine. No change.

Then decided to check the "accordion" air intake tube between the air cleaner and the engine. Felt like the end by the air cleaner was not quite right. (I had to remove the air cleaner housing to access the transmission mount and I flexed it up and to the left and strapped it out of the way with a bungee cord when I did the mount replacement.) I put it back on right...or thought so...and started the car. The engine took off like a jet fighter....4000 rpm or more....I shut it off wondering what the heck I did. So then it was messing with both ends of that air intake and the hose clamps until they were both perfect. The rubber flange kept curling under itself. Once I had both ends perfectly placed and clamped crazy tight I tried again....smooth idle around 1000 rpm. No more high idle....what's more, when I backed it up and hit the brake, it locked up tight.

Took it out for a ride...brakes were perfect.

Apparently, all the brake problems after the motor mounts was just my flexing the air intake line when I pulled the air cleaner housing up...it was just off the flange enough to screw up the vacuum enough to affect the brake booster, but not enough to allow the engine to race. I had noticed that every time I pumped the brakes, the RPM climbed a bit up to about 2000 rpm and that seemed weird. Now it all kind of makes sense.

Now, all is good...except the clunking is still bad. Might be that last motor mount on the passenger side middle, or another problem yet to discover, but I'll get there.

 

the right side lower strut will be ruined if you did not perform a engine mount adjustment procedure.. and you will have excessive vibration compared to doing the adjustment procedure