Hi all, my mom has a 1999 dodge dakota Sport 5.2, (extended cab),

I'll try and start from the beginning and see if I happen to make it into a sensible description.

One day about a month/2 ago, we drove around a rather tight corner, a "check gauges" light came on, stayed on until the corner was over (about 3 seconds) we were puzzled by it and decided we better check the basics, checked the engine oil and it was not visible on the dipstick , however we knew that we had filled it right up last oil change.We researched the internet and came across a recall for the plenum plate/ gasket causing oil loss, turns out that was our problem. We ordered a replacement from Hughes Engines outlet near by, and installed it, ensuring to not get crud in any where, and cleaning stuff up as we went (intake manifold, change injector rings, etc.) Got it all back together and popped the wire off of the starting coil and it (the coil wire) was rusted to the point it was falling apart, so got a new set of wires from Canadian tire and changed them all, labeling as we went to ensuring to put the correct ones on etc. (didn't change the plugs as we changed them a month before that, when we did change them we noticed that number 3 and 8 were blackened). Since the plenum plate and plug wire change, we have been noticing a slight, surging ever so often, it feels like the vehicle is decelerating when it shouldn't be (foot is still steady on the gas) and lasts only a second then back to normal, and as this is happening the RPMs go up about 300(not thousand) or so, but there isnt any torque to go with it. This happens every so often sometimes once sometimes twice in fast succession, then disappears for maybe 15 minutes maybe even and hour when starting from cold , then slowly it would get a little more frequent to the point its doing it every 2 minutes or so (although sometimes totally disappears for a half hour or so). when driving it about a week ago, the CEL finally came on, we got the code reader out and it read P0203,(number 3 cyl). we thought ok, must be an injector that got stuff jammed in it. then we drove it again about 2-3 days later, (after having cleared the code via the reader), drove it for about 2 hours, got home and the CEL was on again, got the code reader out and now there was P0203(Cyl 3), and P0204(Cyl 4), codes up, now we were wondering if it was the injectors getting plugged or not, or something else? now we cleared those codes, drove it again for about 2 hours today, got home with the CEL on again (note that its still doing this surging action every 2 or so minutes all the time, and the RPM needle is still jumping up 300 each time as well. ) Put the reader on it and now it has codes P0203, P0201,P0204,P0205,P0206, and P0208. ( numbers 3,1,4,5,6,8 cyl).
http://www.obd-codes.com/p0203
http://www.obd-codes.com/p0201
http://www.obd-codes.com/p0204
http://www.obd-codes.com/p0205
http://www.obd-codes.com/p0206
http://www.obd-codes.com/p0208

Is this a distributor cap problem? is this a injector problem? A PCM problem? etc
Thanks for any help you may be able to provide.
Donnyh13

 

I'm calling a plenum leak or a cracked plenum

My other guess is the crank position sensor or both

I say the plenum because of how its running sounds like an air leak to me

Especially because its affecting every cylinder with codes for all of them

 

It's hard to calla plenum leak on a replaced plenum, it's pretty hard to screw that up. Doesn't sound like the crank sensor, it would be running much worse. Being sporadic, I wouldn't place it in the valvetrain. Maybe the fuel system. Ignition a far cry maybe, but more towards the coil and less towards plugs/distributor.

What catches my eye is that the RPM's go UP 300 or so, but no power with it. That sounds to me like running lean. On racecars, we use lean-out valves or fuel cutoff valves to lean the motor out, brings the RPM's up and gets heat in the motor.

 

Thanks both of you very much for your quick and helpful replies. It is much appreciated.

The Fuel injectors have never been changed, just the rings as stated above, they were tough to get in, however to grab the wire connector, you can swivel them very easily, could it be that they are not completely seated? However they look to be up to the same rust spot, or perhaps they swivel easily because of being broke lose when we took them out (where as before they were corroded in from never being taken out).

Would you recommend us to put each inject in on their own off of the rail to ensure they are seated correctly? or would that just be looking for more trouble with junk falling inside each injector? (we put the fuel injectors in after they were connected to the rails, we pushed them down and heard somewhat of a pop, and swiveled each to ensure the O ring was in its slot correctly)

Thanks for the help.
Donnyh13

 

Try a new coil they are cheap just a cheap aftermarket one.

Are your headlights dimming on you at all or go brighter as you rev it up?

You may want to check how good a spark you are getting if you have a spare sparkplug on hand pull one cable off and attach the sparkplug and check the spark don't forget you need to ground the plug or it will not spark.

 

I don't think it's the injectors. It wouldn't be intermittent if it were. If the o-rings weren't seating, your truck would be in the graveyard like User's (had an o-ring leak and it sprayed fuel on the motor and exhaust, burned his truck to the ground).

On the topic of going lean, I suppose that the intake manifold may not have seated to the cylinder heads or that something went wrong with the gaskets. Since the plenum compresses between the plate and beer keg, it's hard for me to think it would leak after replacement.

 

It's unlikely to be the coil wire.

When you replaced the injectors, did you lube the o-rings with anything? I'd be curious as to the pressure on the fuel rail - just in case it's something else like the fuel pump failing. You can rent a pressure gauge from most parts stores to test.

 

Hi all, your responses and ideas are very appreciated. Thanks
Ok so we have done a few tests as suggested,
-The fuel rail pressure is holding steady at 50 PSI, and once the vehicle is shut off, it only dropped down to 45 PSI after about 7 minutes .

-We tested each spark plug wire via the method posted above, and all have a good spark.

- We lubed each injector "o" ring slightly with a thin coating of Vaseline when each side was put in. (while attached to the rail).

- We will look into ordering a new coil.
-Any tests to see if it is working correctly without a computer?

- No dimming or brightening of the headlights when the vehicle is reved up.


- Sprayed ether, (starting fluid), around the intake manifold gaskets etc and it did not cause the vehicle to rev up, so, maybe unlikely that it is an intake leak/ fuel injector leak?

Thanks
Donnyh13

 

It's odd that only two cylinders aren't tripping a code.

Pull the connectors on the injectors and clean them with an electrical contact cleaner. Make sure they are seated, tight.

 

Hi all,
well We found the problem it seems, . Went to town this morning after having cleaned the injector connections, still did the sputtering, throwing codes for cyl 3 & 4 then again for 3& 4 then for Cyl 2, 3, 6, got to town, bought and changed the coil, still did the sputtering although perhaps a tiny bit better??
Drove it for a while and decided to go back to the auto parts place and get a distributor cap, as we had read previously one guy suggested it might have been that for someone having similar problems as us. didn't install it right away and drove half way to the next town to pick up our mail, no codes were being tripped but still occasional revs with torque loss. .. Decided to throw the new cap and rotor in to continue . Threw it on (although the old one wasn't really in bad shape or pitted), installed it and it has ran smooth ever since, there is the possibility it went dormant for this time,... ?,, but I think we might have actually found the problem. It's an hour drive back home and nothing bad happened , so looking very promising.

Thanks again for all of your help, it is very much appreciated.
Donnyh13