2005 Dodge Stratus has a clanking sound under engine, mechanic checked engine OK, sounds like loose bolt inside, someone said it sounds like an exhaust problem.

so what else is loose
check stabilizer bushes , bumper bar bolts , grill fittings , external lights , engine mounts , loose splash pan under front, mud flaps , inner guards loose , battery fitting, bonnet latch tight , body insulators on chassis frame , rusted body panels

Best you watch a video on a similar motor

Basically get under the car & remove the bolts
holding it on.

if you have a certain model of stratus there is a fan under the intake on the 2.4 engine. this fan blows air into the exhaust for emissions purposes. the circuit on these fans have a problem with not shutting off. i believe the dodge dealer installs a resister in this circuit to make it shut off. it can make your battery go dead if it dosnt shut off

You need to proof read your message. Look for a vacuum hose off. Let someone start it you with the hood up listen for a hissing sound. Most times they come lose when you've had work done in the area of the motor. If that is not the fault check for a code with the ECM.

this does sound like theres a loose line tapping the engine/frame,during warm up the engine idles faster which could make it vibrate faster causing the the clanking or tapping noise,if this has started after trans fluid change,then check the lines running from the trani to radiator sometimes the service person might bang into something causing plastic clips that hold the lines to break,try getting under it and have someone start the truck and listen to see where it's coming from also hold the lines & see if the noise stops,the service guy could have unbolted something & never put the bolt back causing the clank ex.line may have a clip holding it thats bolted to the trani pan ?good luck

Must not have been much of a mechanic. If the engine runs and sounds fine sometimes and other times it doesn't then it does not sound like a mechanical problem with the engine. Sounds more like a issue with either the ignition system or fuel system.

I did the same job last week and I managed to get a box ended wrench in from the front and get on that bolt just enough to turn it a hair. It took me about 20-30 minutes to remove it and get it back in place and it was a trick to get that little ****** started again, but it can be done. HINT: Get someone with small fingers to help you. My knuckles are still bleeding.

~Ed Hauk

Check the ASD relay in the under hood power distribution box. This powers the ignition system . Do you know what a relay is, how to test it ? Videos on youtube .

Sounds like your mechanic messed up somewhere. I'd take the car back and demand he fix it.

Almost sounds like a possible valve spring problem, That is sending out harmonics to the computer to activate the rev limiter. good luck