Piston Slap: Ain't Got No Problem With Coke!

Sajeev Mehta
by Sajeev Mehta
piston slap aint got no problem with coke

Brian writes:

Hi Sajeev,

I have a 1999 Nissan Frontier. 207k miles, 2.4L four cylinder. I have a Service Engine light which comes on AFTER driving for 30 minutes, parking it and letting it sit for 30 minutes. When I come back and start the truck I get the vibration and Service Engine light. The code is a P0303, i.e. cylinder #3 misfire.

I replace the plugs, wires, distributor cap and rotor. Made no difference, still have the same problem.This repeats just exactly the same each day. Occasionally the cylinder will start functioning again as I drive and vibration will go away but the light stays on. Had the injectors flushed, no difference. Nissan seems to think it’s carbon in the intake (EGR Port).

I doubt that, but maybe the injector or the wire harness? Seem to have the problem after the engine gets warmed up and then parked for 15 to 30 minutes. Because it doesn’t do it when the engine is started cold at the first start of the day.

I haven’t tried it yet but I’ll bet at the first start of the day I could drive it indefinitely and it wouldn’t have a problem as long as I did not shut it off and let it sit, and then restart it.

Sajeev answers:

Why do you doubt what the Nissan mechanic said? Oh yeah, the completely valid, long-standing mistrust between vehicle owners and the people who work on them.

Which is fair…but after all your previous (and good) repairs…you can’t casually dismiss an EGR problem like that! It is, more than likely, the heart of your problem, even though it is hard to tell at this mileage. You probably have multiple problems and everything you’ve done so far is money well spent in my book. Sadly, obviously, the next wear item, the EGR system needs attention.

EGR systems can do some bizarre shit to your ride. Put another way, this guy on this Honda Prelude forum said, “you’d be surprised wat codes your ecu will throw all because of egr problems.” Tru dat.

It’s time to clean or replace the EGR valve. And clean the (intake manifold) ports that feed the EGR its precious exhaust gases. At this mileage you could have severely coked up/blocked up EGR ports, and the valve could be well past it. My advice is the same as the Nissan Tech, clean the valve and the ports (carb cleaner and a toothbrush, a wire brush or a screwdriver for the real bad stuff, WEAR GLOVES) and if the problem continues, replace the EGR valve.

Best of luck!

Send your queries to sajeev@thetruthaboutcars.com. Spare no details and ask for a speedy resolution if you’re in a hurry…but be realistic, and use your make/model specific forums instead of TTAC for more timely advice.

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3 of 13 comments
  • Jz78817 Jz78817 on Jul 06, 2013

    wow, I'm impressed. the "miracle additive" shills showed up in the first comment.

    • Sajeev Mehta Sajeev Mehta on Jul 07, 2013

      While I do like Seafoam, in this case I really believe a manual cleaning and possible EGR valve replacement is worth it. Why spend $7 on that can when you've done over 200,000 miles of hot coking action...that money is better spent on couple cans of carb cleaner.

  • Art  Vandelay Art Vandelay on Jul 08, 2013

    I had a similar issue that was caused by the EGR system, but wasnt actually the EGR. Not sure on the 2.4 but on my Toyota inline the EGR cooked a portion of the wiring harness which caused a similar issue to that which you describe.

  • Nrd515 I bought an '88 S10 Blazer with the 4.3. We had it 4 years and put just about 48K on it with a bunch of trips to Nebraska and S. Dakota to see relatives. It had a couple of minor issues when new, a piece of trim fell off the first day, and it had a seriously big oil leak soon after we got it. The amazinly tiny starter failed at about 40K, it was fixed under some sort of secret warranty and we got a new Silverado as a loaner. Other than that, and a couple of tires that blew when I ran over some junk on the road, it was a rock. I hated the dash instrumentation, and being built like a gorilla, it was about an inch and a half too narrow for my giant shoulders, but it drove fine, and was my second most trouble free vehicle ever, only beaten by my '82 K5 Blazer, which had zero issues for nearly 50K miles. We sold the S10 to a friend, who had it over 20 years and over 400,000 miles on the original short block! It had a couple of transmissions, a couple of valve jobs, a rear end rebuild at 300K, was stolen and vandalized twice, cut open like a tin can when a diabetic truck driver passed out(We were all impressed at the lack of rust inside the rear quarters at almost 10 years old, and it just went on and on. Ziebart did a good job on that Blazer. All three of his sons learned to drive in it, and it was only sent to the boneyard when the area above the windshield had rusted to the point it was like taking a shower when it rained. He now has a Jeep that he's put a ton of money into. He says he misses the S10's reliablity a lot these days, the Jeep is in the shop a lot.
  • Jeff S Most densely populated areas have emission testing and removing catalytic converters and altering pollution devices will cause your vehicle to fail emission testing which could effect renewing license plates. In less populated areas where emission testing is not done there would probably not be any legal consequences and the converter could either be removed or gutted both without having to buy specific parts for bypassing emissions. Tampering with emission systems would make it harder to resell a vehicle but if you plan on keeping the vehicle and literally running it till the wheels fall off there is not much that can be done if there is no emission testing. I did have a cat removed on a car long before mandatory emission testing and it did get better mpgs and it ran better. Also had a cat gutted on my S-10 which was close to 20 years old which increased performance and efficiency but that was in a state that did not require emission testing just that reformulated gas be sold during the Summer months. I would probably not do it again because after market converters are not that expensive on older S-10s compared to many of the newer vehicles. On newer vehicles it can effect other systems that are related to the operating and the running of the vehicle. A little harder to defeat pollution devices on newer vehicles with all the systems run by microprocessors but if someone wants to do it they can. This law could be addressing the modified diesels that are made into coal rollers just as much as the gasoline powered vehicles with cats. You probably will still be able to buy equipment that would modify the performance of a vehicles as long as the emission equipment is not altered.
  • ToolGuy I wonder if Vin Diesel requires DEF.(Does he have issues with Sulfur in concentrations above 15ppm?)
  • ToolGuy Presented for discussion: https://xroads.virginia.edu/~Hyper2/thoreau/civil.html
  • Kevin Ford can do what it's always done. Offer buyouts to retirement age employees, and transfers to operating facilities to those who aren't retirement age. Plus, the transition to electric isn't going to be a finger snap one time event. It's going to occur over a few model years. What's a more interesting question is: Where will today's youth find jobs in the auto industry given the lower employment levels?