I have a 2006 Chrysler Sebring Convertible 2.7L engine. Replaced water pump and spark plugs. We triple checked the alignment on the chain and are sure the timing is fine. Car started right up. Now running rough idle and engine light comes on. Codes read misfires on 1, 3, and 5 cylinders. Any help?
Question.
How many timing chains does the engine have? (Some V engines have 3 chains)
Does the engine have a balance shaft?
Sure sounds like the timing marks are off, or something is out of phase
Could be an assortment of problems. Maybe a little more background would help the experts here. Why did you replace the water pump and spark plugs, and why did you check the timing chain alignment?
Your engine has the primary timing chain which drives the water pump. But it also has the secondary timing chains which operate the cams. One of the steps in this prosedure is to rotate the engine by hand to make sure there’s no valve interference once the main timing chain is installed.
Tester
Only removed the main chain to remove the old pump. Water pump was leaking and needed to be replaced. Boyfriend inspected the plugs while we had the car open and decided those needed to be replaced as well. We marked the cam’s to ensure they were aligned with the timing marks on the main chain.
We rotated the engine by hand several times and the marks came in lign each time.
I had some of the same issues (among others) with my 2001 sebring a few years ago. I ended up changing my camshaft position sensor and replacing an ignition coil. Not too difficult a job but if you’re not getting a code for the sensor then it’s probably not the sensor.
(correction: ignition coil not cylinder)
It sounds like you’ve verified the valve timing is matching up to the crankshaft properly. I’m sure you understand if that was off, the symptom you are reporting would be expected. But at this point based on what you say we have to assume the valve timing is spot on. (For future reference, it’s a good idea before removing a timing chain to always manually rotate the engine a few times and carefully observe and make written notes how the marks line up as you do this. Sometimes the procedure to align the marks isn’t as intuitive as it should be due to the way the engine was manufactured.)
If it is not the valve timing, then what could this problem be? hmmmm … I’m assuming the idle was fine before the water pump exchange, and there were no mods to the fuel system, the PCV, the EGR, or the exhaust system. There’s a chance something was about to go south anyway, and it happened to choose this time to do it. In which case I’d probably start by verifying all the routine maintenance is up to date per the owner’s manual.
But that seems less likely than something you & the bf did while changing the water pump. My first guess is the spark plugs. Did you double check the gap of each one? Are you certain the new ones are the exact part number spec’d by the manufacturer for this car? Are they the same part number and brand as the ones you replaced? If you were told to use that particular spark plug by the retail parts place where you purchased the new plugs, and it doesn’t match up with what the manufacturer recommends, that would be the first suspect. The retail parts place recommended to me the wrong plug for my Corolla for example. I insisted they order up the correct NGK plug from their warehouse, which they resisted as it causes them more work, but eventually they agreed.
Another possibility is that one or more of the new plugs are faulty. This is not that uncommon, even with name brand plugs. Some brands are worse than others. I’ve never had a problem with NGK plugs, but I have with some of the others. The quality control in the offshore plants where many replacement auto parts are made now-a-days is not so good. Maybe put the old plugs back in and see if the idle returns to normal and smooth.
My final guess is that some high voltage wires were damaged in the spark plug replacement process, or if you have the coil-on-plug technology, a coil could have been damaged too. Or the wire order was accidentally switched. Maybe double check all that.