I had a small wreck Tuesday with some minor front end damage mostly top damage. I’m looking for ideas of what has happened mechanically as the wreck wasn’t even that severe. The impact was a bit hard but still not much damage visibly.

So start the car it idles up to 2000 rpm slows down to its normal 800 or so within a few seconds & it stalls. I unplug the MAF and the car idles up to 3,000/4,000 rpm’s, however it does not miss nor does it stall. I thought maybe it’s the MAF but why would it idle so high? When putting the car in drive with MAF unplugged I get reduced engine power message on the dash but the car still never stalls. Hook the MAF back up and stalls. I have also noticed that my brake pedal is stuck to the floor, at times when pushing it the car will accelerate in rpm’s or when driving home I would hold the brakes to the floor and the car would try to accelerate? I have wondered about the throttle body as it was close to the impact point. I have also unplugged the battery and plugged back again. Car has no issue with starting and I would say fuel pump however you could keep it running and drive it if need be. Any idea why the brake pedal is to the floor?

 

All these problems & it’s not even that bad!
When the wreck happened I drove the car off the road I put it in park & it started missing and then stalled & that’s the last time it ran well. The ac condenser is busted but the radiator and hoses are all fine even.

 

Also I’m sitting at 150k even .. coils & plugs replaced at 130k Delphi coils & NGK plugs. After leaving the battery off for awhile the brakes have freed up some but still mostly to the floor. I have checked all fuses to make sure they were seated well. All fluids checked & good. Ac condenser of course is toast but will take care of that later on. I noticed that maybe the gas pedal looked a little lower to the floor than usual am going to do the push pedal 5 times reset and see how far it goes down.

 

Bad knock sensor? Noticed it’s down and under the throttle where the car took the biggest blow.

 

Wrong spark plugs, AC Delco 41-103 iridium plugs. Tighten the 4 bolts in the under hood fuse box. Check for loose or damaged wire harness. Inspect the rubber elbow at the throttle body for damage.
Glad you’re ok!

 

5 time pedal push reset ? Never heard of such a thing on a HHR.
As Oldblue stated, wrong plugs. Ecotec engines only like the AC Delco Iridium’s.
Also. You should pull the codes. I’ll bet there are some in the OBD system that will point you to the problem.

 

Pretty sure NGK makes the plugs for AC Delco and they are identical.I have even seen the NGK mark on plugs sold as AC Delco.

 

The only code is for an EVAP leak which has been the code store for quite some time. I assumed it was the gas cap as it untwists and leaks some.

Doesn’t appear to be any engine damage anywhere just to the ac condenser, the ac line has barely pushed against the throttle position sensor on the throttle body.

the plugs are ruthenium and I have been running them for over a year. The Delphi coils seem great, peppy car & I’ve had several people say it runs so quiet no vibrations has been one of the quietest engines I’ve ever had. Very smooth and great sounding. Until recently sadly. I was thinking the knock sensor possibly sensed the impact and has malfunctioned perhaps? I’d hate to fire the part cannon. Am going to pull up on ramps tomorrow and inspect the underside for any damage.

 

A couple of things to take a look at.

The plastic fitting where the vacuum line connects to the brake booster. They have been known to crack or even break off.

The section of firewall that the pedals mount to. This section has been known to break loose from the rest of the firewall.

Probably neither of these are the problem, but it's free and easy to have a look at them.

 

The throttle body is in need of a good cleaning or replacement, the butterfly plate is open to far.