Timing Belt Replaced--Check Engine Light Afterwards

I had my timing belt changed for my 2001 Honda Civic on Friday at 110K miles. Before I took the car into the shop, there were no problems. Ten minutes after driving away, the check engine light came on, and the car had trouble running and starting later in the day. I took it back to the shop that replaced the timing belt (& water pump, and other belts) on Monday, and they said that the code indicated a malfuncton with the crankshaft timing sensor, which needed to be replaced to the tune of about $300 for parts & labor. They said the timing of the light coming on was coincidental to the timing belt change, but I was skeptical. I took it to another shop, and they say that the timing belt change was probably done improperly. My first question is regarding the coincidence of the sensor problem and the timing belt change–does the first shop just have bad luck or do bad work? Second, if the first shop did screw up, what should I do?

That sounds like some wild guessing by the second shop. Yes, the crank shaft position sensor problem could be co-incidental. Co-incidences do happen.

I am not exactly sure where the Crank Position Sensor is located on a Honda Civic. But, on most engines it is located in the same area as the crankshaft nose where the cam timing belt is located. Some actually use the crankshaft cam cog wheel to generate the signel. It is possible that something was not assembled correctly or the sensor was damaged during the replacement. Usually the cam cog wheel does not have to be removed unless the seal behind it has to be replaced because of oil leakage.

Usually the engine will not start if the CPS signel is missing as that is used to set the ignition and fuel injection timing.

Get back to us when you finally get this problem solved and fixed.

I just talked to the second shop, and they noted that the signal is likely not coincidence because the sensor or the connection to the sensor (I don’t really unerstand because I know little about the workings of cars) would be exposed while changing a timing belt. The codes were reporting two possible error regarding the crankshaft (heck if I know what they really mean), but to fully check what’s wrong, however, they would need to take apart the timing belt area and then reassemble (at a huge cost). They only charged me $40 for the diagnostic and said that I should definitely take it to the first shop that did the timing belt to complain and request the necessary repairs.

Follow up: On Alldata I found that that the crank position sensor is bolted straddling the timing belt and senses a cogged wheel on the outward side of the cam crankshaft cog wheel. It looks like the sensor has to be removed to get the belt off the crankshaft cog wheel. It is possible that the sensor wheel is removeable to get the belt off. Your second shop is right. The covers will have to be removed and the presence of the sensor wheel, postioning of the sensor, and the state of the connection and wires verified.

Sorry about the additional cost but hopefully the original shop will reimburse you for the cost if they are unwilling to go back in a check their work.

Thank you very much. I used the information from the second shop and your advice to confront the first shop. They admitted that while replacing the timing belt, one of the other belts also being replaced (with the water pump) had broken and damaged the sensor in some way (the mechanic admitted to this, but the front desk guy had led me to believe otherwise). They agreed to fix it free of charge, and I’m going to try to get my $40 for the other shop’s diagnosis too. I’ve never been so disappointed in a shop–they (the sales guy) tried to get over $250 out of me for THEIR mistake.

Good for you!

I just did the timing belt on my 2003 civic myself. The sensor you are talking about is on the bottom half of the engine and is a little black thing that can easily be damaged if you don’t move it out of the way. check out my diy here:


and you can sort of see the sensor you are having issues with near the bottom sprockety looking gear. It specifically says in the shop manual that you need to un-bolt the sensor without taking the wires off, and that it needs to be carefully handled so as not to get damaged.

Good luck - power to the people and to you for sticking to your guns and forcing the issue!

Changed out Honda Pilot Timing Belt at 101000 miles. CEL, VSC, VTM lights all came on as I pulled out of garage. Did battery disconnect reset. Drove 60 miles, CEL and VSC came on. Reset again and drove a bit. Came on again. Then CEL started flashing and car shuddered. Stopped and restarted and CEL and VSC came on but again drove fine. Checked every connection under hood. All good. Last test before dealer, checked timing belt job. Appeared front cam off one tooth. Reset belt and ran engine a few minutes. Checked again and all lined perfect. All lights now out. It is hard to get the tension to the right as you install the belt. I put a 17mm wrench on back cam so I could jiggle it a bit to get belt in correct notch. The belt needs to be tight with no slack from back cam forward before pulling tensioner pin. We thought is was but as I recall, it did deflect easily. Bottom line, “one tooth matters!”

10 Years later and absolutely nothing to do with the original problem. Which by the way was solved 10 years ago.

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I am about to change the TB on my 1999 Civic, and found the discussion useful. In this case, I will take special care to avoid the two problems cited.

Sometimes a revived thread is helpful to some readers.