I have a 1998 318 Dakota 5-speed that I bought used 3 yrs ago.
Since day 1 it has had an engine rattle when I drive at low ( under 1200) rpm or when going up hills. It comes and goes, doesn't seem to matter what the weather is. Sometimes it's barely driveable, other times it runs great, but most of the time its there at least a little bit.
I took it to a garage and they hooked it up to some meter and drove it around and said the timing doesnt change when the rattle happens. That's all they could tell me, that it probably isn't a slipping timing belt because the timing doesnt change. Other then that he went on to suggest a lot of " maybe if we replace this or that or the other thing"
Even the Chrysler TSB has about 6 "maybe try this" kind of things such as plug wires, cooler thermostat, cooler pulgs.. all this stuff would mess up my performance and/or milage.
The truck has no anti-knock sensor.
A friend said he read somewhere that a sensor needs to be by-passed.
I can't afford to try 50 different things to fix this problem.
Does anyone have a real solution to it??
I really want to fix this before it hurts my motor, I love my Dakota!

 

Correct me if I'm wrong, but these things have timing chains, do they not? I know my 86 does.

Try running mid-grade or premium gas for a tank or two.

Cooler plugs shouldn't hurt performance, cooler t-stat will help. The reason the stock t-stat is 195 is for emissions. Have you done a full tune up on it? Plugs, wires, cap, rotor (get good ones, brass contacts, not aluminum), etc.?

 

NAPA lists timing chain for '98 5.2L, and the '01 Ram service manual lists timing chain for 5.2L (I don't have a service manual for a '98 Dakota, just 2001, and they didn't have the 5.2L that year). So you are correct.

 

can you describe the noise at all? where is it coming from? is it metal on metal? driving at very low rpms will inherantly bring a low engine vibration/rattle because the motor is not at a high enough rpm or does not have the proper clutch engagement for the torque you are placing on it. also, check a couple simple things. how many miles does it have on it and what was the previous owner using it for? check motor mounts to make sure your bushing havent worn down and are causing a low end vibration. do a complete tune-up. if your truck is a 98 i am sure it needs one if you havent already.

let us know how it works out.

 

Sorry, i should have mentioned it is definately an engine noise, preignition. It not only does it at low rpm ( thats where it is worst and most common) but also does it a little at higher rpm.
Thats why it was suggested to me at the garage about cooler plugs and cooler thermostat. But to me that sounds like it is treating a symptom rather than the root cause. But then again maytbe that's all I can do. When I bought it the thermostat was a really copld one, had no defrost or heat in the winter, so I guess the previous owner put in a colder thermostat to get rid of or reduce the noise. I bought the truck in the fall and almost immediately changed the thermostat so I could have some heat.
Truck has 218.000 km on it, I change oil. filters etc regularly. Only thing I havent changed is the wires. They are stock Mopar wires.
thanks for the advise everyone !

 

Do you see anything common when it happens? Is the truck cold/hot, full/low on gas? Does it happen if you take of slow? What about if you throttle it?

If all you have done is oil/filter in the years there is alot you should do. Not all related to your problem, but gen maint. If I had your problem I would start with a full tune up...wires, plugs, cap, rotor, check the tip of the coil, make sure its in decent shape.

Also you mention it happens mostly under 1200 rpm correct? Is it only happening on take off? I have an auto but, it idles at 700rpm, general cruising stays at about 1800-2100rpm. You shouldn't really be under 1200 rpm that much I would think, especially going up hill. When I had a stick, I know that if I throttled it when I was in too high a gear for what speed I was going it would bog down and you could hear a tinking sound in the motor. Driving in too high a gear can bad just like maxing a gear out can. Does it sound like that, when you shift too much and it just bogs?

2 cents

 

i have a 1999 5.2l and the spark plug wires were leaking when i got it a few months ago. i would start with a full tune up and get your basics covered. if you haven't already; replace the cap, rotor, plugs and wires. then clean/replace your air filter. i wouldn't consider it a repair expense, its just basic maintenance.

 

Thats the mystery, there seems to be no consistancy to it, although it runs best when the motor is cold. No or very little rattle when cold, but when at operating temperature sometimes it will do it, sometimes not, doesnt seem to matter what the weather conditions are. Will happen for sure if i hit the gas hard or go up a hill, although sometimes on the big hill on the way home from work it will rattle like crazy, sometimes just a bit, again doesnt matter what the weather is like.
It idles about 1100.
If I back off the gas a bit the rattle quiets down, but will return if i get on the gas again, so I usually try to hit hills around 1800 rpm or more.
I give it 3 oil changes a year, generally change cap roter and plugs every couple years, I have been using Bosh Platnum plugs. I change the air filter once a year. Have never changed the wires, I'll do it this weekend.

 

Sounds like a serious case of pre-detonation which can burn a hole in the top of your pistons!!! I would try the suggestion to run a tank of premium thru your Dak. If that cures the problem then we can work from there.
[sm=signs003.gif]

 

Ya thats what IM afraid of, burning a valve or piston.
I did try running high octane gas once, but with the problem not happening consistantly, it was hard to tell if it helped at all, it for sure didn't cure the problem.
I should add that the plugs have been checked and look fine, not hot or burnt looking.
How do i go about finding a plug thats cooler than stock? how much cooler should i go? This is something that has been recommended to me a couple times, thought I'd try it.
I drive a dodge at work as well, 318 ram and it runs about the same engine temp as mine, thinking I might put in a slightly cooler thermostat in mine. 182?