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Rough idle/wont rev past 2000rpm

nobodyfresh

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I just performed the timing chain tensioner repair and now when I start the truck it idles rough and won't rev past 2000rpm when in gear. When in neutral or park and I rev it, it seems very sluggish and takes a while to increase engine speed.

I checked all vacuum lines and electrical connectors and I didn't notice anything disconnected.

There are no codes being thrown and it is able to idle (roughly) for over 20 minutes.

I'm bringing it to the dealer tonight if I can't fix it. I'm so frustrated!

Any ideas?
 



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Are all the plug wires on correctly? Could also be vacuum or timing related.
 






in the interest of my sanity could you post which terminal on the coil pack goes to which cylinder? I cannot find a diagram of it.
 












Thank you for the prompt reply. Unfortunately, my plug wires were correct according to the diagram on that website.
 






Did you remove any of the chains? If so, well...uhh...it might not be good news. That's MIGHT not be...not necessarily fact.
 












The dealer looked at the truck today and came back with the diagnosis that there is a large vacuum leak and cylinders 1, 2, and 3 were reporting a leakage of 30%, 26%, and 27%.

They want to pull the engine to do the rear tensioners and send the head out to be checked. This doesn't make much sense to me since I never touched the rear tensioner and was very careful not to touch the sprockets or chain in front.

Does this sound like the cam timing was affected?

Could all this be from the major vacuum leak?

When driving it to the dealer yesterday it took a long time to get from idle to 2000rpm, however, once it got to 2000rpm it ran very smooth and powerful.
 






That is some serious leakage. Did they say where it was going? They should have been able to tell. Was the air leaking into the crankcase, intake, exhaust, or radiator? That will tell you what's wrong.

That's a darn good shop that will do a leak down test for you as part of a diagnosis.
 






The dealer wanted to replace the whole engine and thought that the rear chains were the ones messed up. I didn't like that idea so I told them just to fix the vacuum leak. They then said it would be about $700 to do the intake manifold gaskets, $150 of that being parts. Once again, I didn't like that idea so I opted to just pay for the diagnostic work and try to fix it myself.

They did identify the hose that runs to two locations to the bottom of the upper intake manifold (with those little white clips) was damaged and needed to be replaced.

I guess my question is if I have a massive vacuum leak would it cause the problems I'm having?
 






will it idle in drive, with your foot on the brake, when the engine is warm?
 












strange... i had a minor leak via the EVAP system that would stall out my Ex.

You might have weak vacuum, but I don't think it's from a leak.

Does it cut out at 2000 RPM like a rev limiter?

I'm thinking throttle position sensor (TPS).
 






It's actually kinda interesting. It holds a semi-rough idle for long periods of time. Acceleration from idle - 2000rpm takes a very long time and it feels like there is no power. Once it hits 2000rpm it has steady power and runs OK.

When revving it in neutral/park it can get over 2000rpm but it feels very sluggish getting there.

There is a known huge vacuum leak so I keep thinking about that as a cause. I just hope it is the only cause....

I don't really know how the timing could be off like the dealer says since I know for a fact that the sprockets nor chain did not move while I was doing this repair.
 






I picked it up from the dealer and it started right up and idled sorta rough. It had a decent amount of power and ran reasonably well, regardless of rpm, until it warmed up. Once it warmed up the same problem came back. When idling I can hear the vacuum leak from inside the car and when I step on the gas it goes away.

Are these things indicative of cam timing problems or the vacuum leak? I'm going to let it cool down and take it out again to see if it repeats this behavior.
 












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