Friday, July 22, 2016


Warning – no Corvair content in this post. What does follow is a missive on the frustrating follies of an amateur mechanic.

Short back-story. Our adventure began on a quiet day in early February when Victoria’s GMC Acadia had a timing chain failure. The vehicle was 3,000 miles past GM’s warranty on this issue. The local mechanic told her it’d be $5000 to replace the engine – not willing to quote just replacing the chains because he didn’t know how deep into the engine he’d have to go to complete the repair. We chose the less expensive route of fixing it ourselves. Four months of sporadic weekend and evening thrashes resulted in the car going back on the road with five check engine codes and a puddle producing transmission fluid leak. Cleaning the MAF sensor (one of the codes) and putting an o-ring in the suspect transmission line joint didn’t do a thing, so we bit the bullet and delivered the car to the local mechanic to sort out and deal with the problems.

Today Victoria retrieved her repaired car and was told a small piece of foam had become lodged between the upper and lower intake manifold pieces causing the air leak triggering many of the codes. I apologized profusely to Victoria while kicking myself over my lameness for having this happen. She was gracious in reminding me there were other issues that the mechanic needed to deal with (new transmission line seals, leaky O2 sensor, and a malfunctioning manifold control valve).

Now we wait and see what happens next. Do the codes stay away? Are all the leaks alleviated? Does the A/C blow cold (we had to have it evacuated in order to drop the engine to do the timing chain replacement)? Time will tell.


  1. Why did the chain fail? I have done a bunch of Saturn chain's but never an Acadia.

    1. This was a known issue with GM. The chain stretches and eventually jumps a tooth. GM extended the warranty up to 120k for this problem. This car had its chains replaced (according to the CarFax) at 55k, but it still failed again at 122k.