Rick,
Sorry to hear about your troubles. I once had a bad pinging problem.
Unfortunately I kept it for at least a year and a half before I found the
cause. I did the colder stat, colder plugs, plugwire re-route, wires, cap,
rotor. I found my intake floor wet so I replaced the stock intake manifold
w/the MPI intake (no plenum gasket to blow out). It helped - but not much.
Pinging was still there and I dared to even think about going to the dragstrip.
'93 octane gas was a must - even w/the stock computer. Drove me nuts.
Replaced the MAP sensor and that helped alot also. But when the seasons and gas
formulations changed - it came back almost as bad as before.
Turns out that I had left out the baffles when installing a set of MP valve
covers. It scared me to think those screws might back out and find there way
into the engine. They just didn't have the right "feel" when snugged down.
Apparently the magnum engines are on the edge of having too much compression -
especially in a heavier truck application. This makes them extremely sensitive
to intake air quality. The pcv was allowing crankcase gases to dilute the
intake charge just a bit more than the stock configuration which resulted in
pinging like a mother. One day the thought just came to me that in the case of
excessive blowby - I would get more oil vapors in the crankcase and suck them
right into the throttle body (yes the MPI intake floor was still sweaty-to-wet
looking). It wasn't excessive blowby but the lack of the baffles duplicated the
problem. Simply pulling the pcv out of the valve cover and plugging it followed
by a short test drive confirmed the theory. It stayed plugged until I put the
baffles back in - now I have it reconnected for a slightly positive crankcase
vent. Never had a ping again since that day.
I now run the MP computer, a new camshaft that I installed 3 degrees advanced.
I still run '93 octane but believe it could handle lower with absolutely no
evidence of pinging.
Another clue I had previously been given (but didn't register at the time) was
when a friend (w/another IndyRam) and I swapped air intakes. He was running an
Airaid setup and I had a K&N FIPK. His worked fine on mine at the time (pinged
before, pinged after 8). But when he put the FIPK on his - it started pinging
like a sob - and his had never pinged before. Apparently just the extra few
degrees of intake air temperature made the difference on his truck. A guy on
the DML just had this problem recently - sorry but I must have deleted that
post.
Did you mention that you have any potential oil residue on the intake floor?
Use a bright flashlight and be sure. Also - have you changed anything from the
stock config? Previous owner? Air intake changed at all?
Don't give up man - the reward of fixing it yourself will bring all kinds of
confidence and the partnership that you "used" to have w/your baby 8).
Latr,
Shane
"Suter, Rick" wrote:
> The saga of my '99 5.2l continues in my mind, but ends in Chrysler's.....!
>
> The dealership after MANY attempts to rid my 5.2 of its ping calls in the
> Chrysler rep that emphatically states, with a straight face that he does not
> hear a ping. At the same time I can hear it plain as day. What a PUTZ! He
> says he'll note it in my file, I say that's an unacceptable answer and that
> I'll be extremely pissed of when the engine blows up at 50k because of
> detonation. He stops short of an apology. In the meantime, the truck now
> runs worse than it EVER has. It stumbles along at anything under 1900 RPMs,
> grudgingly makes ANY power under 3000 rpms and basically runs like a vehicle
> that needed a tuneup 190,000 miles ago! The truck as a mere 37,000 miles.
> I'm out of answers short of driving it through the dealership front window
> then going and buying a Ford. And them's strong words from a 30 year,
> dedicated Mopar owner!
>
> Any help is surely appreciated....
>
> Rick
-- '96 IndyRam-HisIndy-MPI TB Pulleys RTcam MPComp HVoilpump DynaGearDoubleRoller WindageTray CompTAs '96 IndyRam-HerIndy-numbered(#142)"Track Truck" '74 Triple-Black Dodge Challenger Rallye 360 EFI R&D vehicle '93 Dakota CC 318 - soon to be mine 8)
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:02:05 EDT