Hello all, first time poster here. I have a 1999 Dodge Ram 1500 4X4 5.9L automatic that I'm having a huge problem with; it just dosen't want to start without a huge effort!

A little backstory, in case it helps. About a month ago, on the way to work the water pump blew out on the highway. The temperature gauge never went about 210 or so before I was able to pull off the highway. The engine bay did get pretty soaked. Replaced the water pump and gasket, but since then (and since the weather started getting colder) the engine just simply dosen't want to start without a massive amount of cranking on the starter. I'm at wits end here...after doing quite abit of research, I've tried replacing the fuel pressure regulator, the IAC motor, crankshaft sensor...I've checked the fuel rails for pressure and it gets good fuel pressure right away and holds it fairly well. The cap and rotor are brand new, as is the coil and spark plugs. I've tried pulling the plugs to test for spark, and it's getting really good spark at the plugs. I've tried replacing the intake manifold and plenum gaskets (which needed to be done anyways), to no avail. Checked the compression as well, and each cylinder was at 125 PSI. It's also not throwing any codes, and I've tried resetting the PCM after adding the new sensors. Checked the camshaft sensor and MAP sensor as well, and it's reading correctly according to my Haynes manual.

Finally I broke down today and took it to the dealership for a diagnostic test; they couldn't find anything, other than recommending a leakdown test. I'm awaiting word on that.

When the truck DOES start though, which only happens if I hold down the accelerator while turning it over for awhile, it runs like a champ. Even better than when I bought it three months ago, with all the new parts I've thrown at it! Plenty of power, it never hesitates or anything. When it's warmed up, if I shut it off and try to start it back up it fires up easily.

Sorry for the short story, but I wanted to try to get all relavent information in here. If anyone has any thoughts or advice, I'm all ears! Thank you for reading this and any help you might offer!

Edit: Just wanted to add it has a brand new battery in it, since the old one was definatly too weak for the truck. I've tried taking the air box off and spraying starter fuel into the intake, but it dosen't make any difference.

 

I'm thinking one of the sensors you purchased is defective(IAC or crank sensor maybe). What brands did you buy?

 

Pretty much everything I buy is through my local O'Reillys, so BWD for the most part.

 

try the coolant sensor .if it doesnt kick on ether your getting too much fuel maybe a leaky injector.since this all started after an overheat id lean towards the temp sensor being shot ,could be running too rich if the temp sensor reading an incorrect temp.to bad you dont have access to a scanner you could check the temp reading with.

 

What brand of plugs do you have in there? Have you pulled them lately, to see what they look like?

 

I checked the injectors earlier and I believe they're all working fine....as for the coolant sensor, I think there is a way to check that with a ohm-meter so I definatly might try that. Spark plug brand I don't recall for sure, I want to say Champions....they all look good, they're only about a month and a half old or so. No oil or carbon buildup as far as I can see.

I did recieve some pretty bad news on the engine though, the dealership said on the leakdown test 6 of the 8 cylinders had 40%-75% leakage. So at this point it seems I may only have two options, replace the whole engine or rebuild the whole engine....according to the dealership anyways.

 

Did they say WHERE it was leaking? The idea behind a leakdown test is, you can HEAR where the air is escaping... be if valves, or rings. If it is just valves, replace the heads... LOT cheaper than an entire rebuild.

 

They didn't say specificly, but they meantioned they thought the piston O-rings were shot. I'll ask them when I pick up the truck from the dealership, they were fairly vague on the phone.

 

If the rings are shot..... definitely rebuild time.... How many miles on it?

If you end up doing the rebuild, don't bother with the stock heads. Replace them. Crack prone, thin decked pieces of bovine excrement.

 

127k miles on the truck. Trying to decide on what to do at this point...either rebuild the existing engine, buy a rebuilt engine, or find a junkyard engine and go with that. I don't think I have a good chance of finding a 5.9 Magnum though with anything resembling decent mileage on it, and there's no point replacing my beat-up engine with another beat-up engine.