Sorry, I know it's long! I've spent the last two days trying to diagnose a problem with my truck.
My new truck was idling rough and RPM's were running low almost like it wanted to stall. First I checked the battery as this happened with my Jeep and all the mechanics thought it was this sensor or that.
Anywho, battery tested fine so, I took out the MAS(mass airflow sensor) & cleaned it. I am no mechanic and am broke so, cheap fixes are what I have to do. I cleaned the carbon build up from the throttle body & butterfly, cleaned the IACV(idle air control valve) for about 45min.(it was dirty as hell) & said screw it and ended up replacing it. The gasket was gone and it just looked like there was too much build up. Checked for vacuum leaks and nothing!! It still idled like ****! I said screw it and went to bed.
At this point, I'm thinking: bad coil, plugs, intake manifold leak(no visible signs though), fuel filter, throttle body sensor, clogged injector, PVC valve, EGR valve, hidden vacuum leak or bad MAS( I've heard of these being bad and not throwing a code).
Got up this morning, went to the local auto parts store and grabbed my bottle of lucas fuel injector cleaner(next, was going to be the fuel filter). I saw the can of SEAFOAM and have heard good things, just have never tried it. Little fella about my age says he & his mechanic swear by it. It's like a "engine and fuel systems tune up in a can". Directions say to pour 1/3 in the gas tank, 1/3 in the oil reservoir, and let a 1/3 get sucked up through a vacuum line so, it can go across all the cylinders and get down in the motor. I don't like changing the viscosity or formula of motor oil as modern oil seems to be correctly formulated, IMO.
The motor needs to be warm so, I poured about half in my gas tank and filled up with normal 87. It seemed to calm down the rough idle but, still felt like it wanted to stall. I got home and unplugged the vacuum line to the break booster and let is slowly "sip" up the 1/3 of a can so it doesn't spill. It sounds like it wants to die because there isn't much vacuum pressure so, I had to cover it with my finger. Once it was all in, I cut the car off and went inside for lunch to give it time to work it's magic.
About 30min. later, I got my brother to come help me. Tip: if you do this, do it in a well ventilated area & don't immediately drive down the road(cops will think you failed emissions, lol). So, he cranked it up and did a constant rev to about 2,000rpm then held steady at 2,500rpm. He increased to 3,000rpm for a moment, just to make sure it was burning all the buildup, carbon, and gunk out of there. I was amazed at how much crap came out of the exhaust. Def. Not a gimmick product. After about 5min. and a few neighbors staring, I took it on the road for a test drive. You'll wanna wait until
most of the buildup smoke is gone. I was amazed! No hard idle, no low RPM's or wanting to stall. Smooth and quiet motor operation. I spent hrs. and even replaced a $40 valve, when it seems was a clogged injector or buildup and required a $10 bottle of SEAFOAM!
**notice all of the white smoke. That's all the buildup & deposits. It's amazing what fuel leaves behind and how the motor gets caked up over time**
https://vimeo.com/103599094
My new truck was idling rough and RPM's were running low almost like it wanted to stall. First I checked the battery as this happened with my Jeep and all the mechanics thought it was this sensor or that.
Anywho, battery tested fine so, I took out the MAS(mass airflow sensor) & cleaned it. I am no mechanic and am broke so, cheap fixes are what I have to do. I cleaned the carbon build up from the throttle body & butterfly, cleaned the IACV(idle air control valve) for about 45min.(it was dirty as hell) & said screw it and ended up replacing it. The gasket was gone and it just looked like there was too much build up. Checked for vacuum leaks and nothing!! It still idled like ****! I said screw it and went to bed.
At this point, I'm thinking: bad coil, plugs, intake manifold leak(no visible signs though), fuel filter, throttle body sensor, clogged injector, PVC valve, EGR valve, hidden vacuum leak or bad MAS( I've heard of these being bad and not throwing a code).
Got up this morning, went to the local auto parts store and grabbed my bottle of lucas fuel injector cleaner(next, was going to be the fuel filter). I saw the can of SEAFOAM and have heard good things, just have never tried it. Little fella about my age says he & his mechanic swear by it. It's like a "engine and fuel systems tune up in a can". Directions say to pour 1/3 in the gas tank, 1/3 in the oil reservoir, and let a 1/3 get sucked up through a vacuum line so, it can go across all the cylinders and get down in the motor. I don't like changing the viscosity or formula of motor oil as modern oil seems to be correctly formulated, IMO.
The motor needs to be warm so, I poured about half in my gas tank and filled up with normal 87. It seemed to calm down the rough idle but, still felt like it wanted to stall. I got home and unplugged the vacuum line to the break booster and let is slowly "sip" up the 1/3 of a can so it doesn't spill. It sounds like it wants to die because there isn't much vacuum pressure so, I had to cover it with my finger. Once it was all in, I cut the car off and went inside for lunch to give it time to work it's magic.
About 30min. later, I got my brother to come help me. Tip: if you do this, do it in a well ventilated area & don't immediately drive down the road(cops will think you failed emissions, lol). So, he cranked it up and did a constant rev to about 2,000rpm then held steady at 2,500rpm. He increased to 3,000rpm for a moment, just to make sure it was burning all the buildup, carbon, and gunk out of there. I was amazed at how much crap came out of the exhaust. Def. Not a gimmick product. After about 5min. and a few neighbors staring, I took it on the road for a test drive. You'll wanna wait until
most of the buildup smoke is gone. I was amazed! No hard idle, no low RPM's or wanting to stall. Smooth and quiet motor operation. I spent hrs. and even replaced a $40 valve, when it seems was a clogged injector or buildup and required a $10 bottle of SEAFOAM!
**notice all of the white smoke. That's all the buildup & deposits. It's amazing what fuel leaves behind and how the motor gets caked up over time**
https://vimeo.com/103599094
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I have had good results with it but prefer Lucas products.
