Engine toast???? 2003 ES 3.8L

[2003ES]

I have a 2003 Grand Caravan ES with the 3.8L. Runs very rough at idle, code
P1297( no change in MAP from start to finish) comes up.
Local mech. checked compression on left 3 cylinders, 0 in first, 180 in second, 80 in last. He figured maybe the timing chain skipped, bent valves etc.
Anyone have something similar happen? Thanks for any info.

[hcmq]

run from that local mechanic! I bet he doesn't even know what fuel injection is and how it works!

just because the engine is running rough he goes right for a compression test?? sounds shady to me.

never ever let anyone do anything without a written diagnosis of what factory mandated test they ran to come up with what is wrong.

there are 1000's of things that can cause these to "run rough"

you said it runs rough at idle how about while driving?

I won't go into all of the other questions of what needs to be checked until we hear more about what the van is doing.

[2003ES]

Thanks for the reply, I actually trust the local mechanic. It's being taken to a Dodge dealer today since they have no time for further analysis.
The fact of the matter is that at least 2 of the 6 cylinders have little or no compression, which I doubt is fuel injection related. I've heard of the valves gumming up and causing problems on these motors.
I wasn't trying to get it repaired online, just wondering if others have had these symptoms.

I changed the MAP sensor and that did nothing and all the other O2 sensors check out OK, as per their inspection.

[Rick99]

I suspect that the guy's diagnostic process led him to do the compression test which sounds like it was a good move. If there's no compression in a couple cylinders, then something is mechanically wrong with the engine. One could pump air into the sparkplug hole and listen whether the valves are leaking from exhaust or intake, but at this point it seems the best thing would be to take it apart and see what's happening in there and figure out cost to repair vs cost to replace vs value of the vehicle, etc.

Without taking it apart there's not much someone can really tell you. If it needs a valve job and head gaskets, it may be well worth repairing it.

[acton mike]

how was the engine running before you encountered the problem?
was it gradually getting worse or did the problem occur suddenly and it if was sudden did you notice any odd symptoms or sounds

often an analysis of odd sounds/smells/leaks/vibrations that take place before and as a problem i9s noticed can give one a bunch of clues as to what is going on

A compression test will tell you a great deal if it is done right

a cylinder leak-down test takes longer but gives a great deal more information

[2003ES]

how was the engine running before you encountered the problem?
was it gradually getting worse or did the problem occur suddenly and it if was sudden did you notice any odd symptoms or sounds

Everything seemed to be fine before, was running as always. I should hear more today ,hopefully, it's at a Dodge dealer getting checked out.

If it comes down to needing an engine, would a 3.3L fit in there in place of the 3.8L without any major mods?

[acton mike]

i believe the 3.8 is a punched out 3.3
I stand to be corrected by those more knowledgeable

[2003ES]

Broken valve spring is the culprit, according to Dodge mechanic. Not sure why there was little compression on the one cyl originally, but apparently only the 1 with "0 compression" still shows same, all others are good.
Still a $1300 fix.

[UKkid89]

I have an '05, 109,000 miles, we were cruising at 75 when lost power. Mech found no compression in 6. Turned out to be a broken valve spring on 6 which resulted in a bent valve. Also bad intake gasket. All told took two days, 1 for parts to arrive. Totaled $775 at $96 per hour.