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2009 Jeep Compass engine turns but will not start

My upper radiator hose sprung a leak and coolant was spraying. Jeep was overheating so I pulled over and turned off engine. Replaced coolant and tried to restart engine but it wouldnt start. That was Monday last week.

A scan for codes showed only P2017, so I replaced the Intake Manifold Runner Control. I also replaced the Upper Radiator Hose. The codes were erased in the Jeep and engine was tried to start again without luck. Starter turns but engine doesnt run. Check engine light on so checked again for codes but no codes are given even tho check engine light on. Im lost. What to do???

Engines need air, fuel and spark to run. How handy are you? How are you fixed for diagnostic tools? Voltmeter? Compression tester? Fuel pressure gauge? From your post, I’d guess you can operate a code scanner and replace parts but little else. If I’m wrong, please post if you have the tools I’ve listed and we can walk you through the procedures.

If I am correct that your tools and skills are limited, it is time to have it towed to a local independent mechanic who can diagnose whether it has air, fuel and spark and IF there has been any damage to the engine from overheating. Good Luck!

Ive used voltmeters and compression testers. I dont have a comp tester though. I will be checking soon the plugs, to see if theyre wet after cranking and to see if theres spark. Ive never used a fuel pressure gauge but know the fuel pump works as theres a hum in the back when I turn the ignition from OFF to ON. How could the CEL be on yet no codes scannable by the reader?

Because it hasn’t actually started and the CEL turns on if the engine isn’t running to let you know it hasn’t burned out. Please check for spark, pull the plugs and check for wet. If they are wet and there is spark, it should at least try to start.
Since the plugs are out, compression test the engine first dry. If all are OK dry you are OK. If one or 2 is low, then do a wet test with a small amount of engine oil squirted in. If 2 side-by side cylinders are still low, blown head gasket is likely. If both low cylinders now read good, the rings are bad and the engine is on its way out but should still start. If there is spark but no fuel, try a little starter fluid spray. It should fire right up but stall quickly. That tells you its a fuel problem.

Attach a fuel pressure gauge to the test port under hood and just key-on to run the pump. There should be significant pressure 40- 50 psi, I’d guess. Google the proper fuel pressure reading for this car but it should be close to this range.

I’d guess one of the 3 isn’t present, spark or fuel most likely. If you don’t get either spark or fuel, suspect the crankshaft position sensor as a bad one will keep either from happening.

My first guess is the coolant got some part of the high voltage system wet and is now shorted out. It might dry out and fix itself if you wait long enough. Checking for absence of a visual spark at a spark plug would be first up for that one. Second guess – less likely — is the overheating incident caused some internal engine damage. A compression test would be first up for that.

If the engine overheated severely the cylinder head may have warped resulting in no compression, does the engine seem to crank without any resistance?