Accident & Damages -- Question for the gear-heads out there

So, just to meet the minimums, I live in Wyoming, and I drive a 2010 Chevy Traverse AWD. This car has been really good to us and the only issue I have ever had is the Throttle Body needing a regular cleaning (every 6M to a year). Other than that, the car has been great.

Well last week, we were rear-ended by a Suburban, going about 40 MPH. The only visible damage is a annihilated rear bumper, and a small dent in my rear lift gate. When the accident occurred, however, the CEL came on. Car was running just fine, so I finished my drive to work, did my normal day, and then drove home (light still on). I of course noted this in the accident report, etc. Well when I got home, I grabbed my ODB2 reader and plugged it in. It is reading a couple errors, a misfire condition on 1,3,5 cylinders, and a ‘multiple misfire’ code. This issue was not present prior to the accident, but when I took the car in Wednesday to the repair shop for an estimate, he told me that it was more than likely not going to be covered by the insurance, as this issue could not even be remotely tied to the damage from the accident… (Also, forgot to note, the car is running very rough. We opted to garage it and just use the truck while we wait for insurance to come through.)

I am asking two questions of you guys (and gals, where appropriate);

  1. Could you see a misfire issue occur because of a rear-ending?
  2. From some brief googling, the other possibility for this problem is engine sludge. Engine sludge can cause the timing chain to stretch and throw timing off. Apparently it is a ridiculous amount of work to fix too, as you have to remove the whole engine to get to the timing chain. Question: Would there be an easy way to determine if there is sludge in the engine? I change my own oil regularly (5k or so), and I use a full-synthetic for high mileage engines (96k).

I am some-what of a mechanic, but this heavy work is out of my league…I just want to see where I should head with this, as we are a big family and I need the family car back…

Thanks for any input you can offer!

I don’t think the sludge problem is much of an issue here if it exists at all. You could probably change out the valve cover gaskets and visually inspect for sludge. I also think you need to get a new garage since they discount the CEL. A misfire can happen easily after a rear end collision especially if the rear bumper was “annihilated.” It will take an experienced mechanic to find the cause of the misfire so I recommend a good, independent mechanic. I have had the CEL pop on and off during a rough ride over a gravel road in Alaska. I never did find the cause but I cleared the code and it never came back.

What if the tail pipe got bent in the rear end collision and got a kink. This would cause back pressure and a possible misfire.

Missileman and Triedaq

Thank you both. I did not check the tail pipe. I am not sure why I didn’t think of that. I will take a peek at lunch. But I appreciate the reaffirmation from both of you, that I am not going crazy! Again, since this is more of a hobby and not my trade I was more inclined to believe what this guy claimed. I will definitely take it to another service area. You have no idea how much relief you have given me!

Thanks much!

rear-ended by a Suburban, going about 40 MPH

If the speed estimate is accurate, I predict you will find quite a bit of hidden damage underneath the plastic facade. Were you completely stopped when hit?

Has anyone inspected for damage caused by the engine swinging back into the firewall due to the impact? From a cracked plenum to pinched wires there are a great many things that need close inspection before dismissing the likelihood that the impact caused the problem.

Check your fuses. The Coil On Plug ignition coils are fused separately for each bank. Bank 1 includes 1,3,and 5. I don’t know where the fuses for the ignition banks are located so check with your Owner’s Manual.

Also, check for any broken or cut wires as Bank 1 is against the firewall. The engine would have reacted that way with the collision so a wire may have been crushed or the insulation compromised causing a momentary short. There is a ground wire for each bank of coils so check that the ground for bank 1 coils is still intact

Again, thanks everyone for the comments. All of this is extremely helpful.

Yes, TwinTurbo, I was at a complete stop, foot on brake.

The mechanical shock from the collision could damage electronics even though they are at the other ind of the truck. You need to have the entire truck inspected for damage. It is possible that your problems are related. To the accident. If they don’t like it, tell them your neck hurts.

Wow. Join the club. I was hit under the exact same conditions by the exact same vehicle a week before Thanksgiving in 2007. TRUST ME when I tell you there is probably a LOT more damage underneath what’s visible. While it didn’t look bad at first, the rear half of my Buick needed extensive repairs. But, as a silver lining, it was indeed repaired, and is still on the road.

The impact of an accident liker this could damage sensitive electronics in the front of the vehicle…even though the strike was to the vehicle was to the rear.

The misfire could be as simple as the air tube, from the throttle body to the filter box to have a crack or pulled off durring the crash.

Maybe it’s time for a dealer rather that the local mechanic. They may be more willing to claim this damage on the accident. You can always have the badywork done elsewhere.


If a Suburban hit you stopped while the Sub was doing 40, you’re lucky to not be in the hospital and the car totaled. MUST have been much less than 40.

There could have been a glitch in the electrical system when you got hit by the other car. All the jostling of the wires, connectors, fuses, etc. As long as the engine performance and drivablity seem to be the same as before, I’d be inclined to just reset the codes and wait to see if they come back.

This is such a fantastic community! Thank you all so much! I never expected this much response. It is very much appreciated!!

Know That Is A Difficult Situation To Claim A Drivability Issue As A Result Of Being Rear-Ended. I Managed A Body Shop And Dealt With Customers In Need Of Repairs And Insurance Adjusters. What Makes It A Difficult Situation Is That Some People Claim That Everything Under The Sun, That Was Wrong With Their Vehicle Before The Accident, Happened As A Result Of The Accident. Once Bitten, Twice Shy.

Also, insurance adjusters are trying to save money for their insurance company and some are downright cheap. I had trouble even convincing some adjusters that hidden damage was caused by a collision while I was showing it to them and describing it. Depending on the company, some adjusters don’t have much car knowledge or prior car repair experience.

If it is rear exhaust system damage causing it then that should be the easiest case. If it’s something else and a “mechanic” can understand it and vouch for you, then you’d have a chance. A dealer or somebody very familiar with your particular make/model could be helpful.