Cutting out in higher RPM's
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Cutting out in higher RPM's Well, I've been having this issue for a little while now, and haven't really been able to track down the problem. It only happens every now and then, and so it makes it even harder to track down. But, I noticed something about it tonight. I was taking a buddy to his car a little while ago that was out in the country a little ways, and so, while driving on the country roads, the car got cooled down more by the colder, moving air (Temp gauge was only reading a little above 160*). I got on it and, it started cutting out up top again (A little above 6k). When I dropped him off, I sat there and talked to him for a few minutes while he let his car warm up, and so my car warmed up a little more because it was just sitting there running without moving air. The temp gauge was probably reading another 10, or so, degrees warmer when I left. I got on it again leaving, and the car didn't cut out one bit up top. Pulled strong all the way to ~6700rpm's. Then, the temp gauge went back down to where it was before, from the moving air. And so, I decided to get on it again to test it out. And wouldn't ya know, it cut out again. So, I'm assuming the car running cooler had something to do with it. But, I don't see why it should, as the car should already be into closed loop at these temps anyways, shouldn't it? Any help would be much appreciated.
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I'm starting to think it's the 160* t-stat. I did a little bit of research on t-stat's, and it seems a 180* or stock one is actually better for LSX motors, otherwise it may be too cool to properly burn all the fuel. So, maybe that's my issue, since it was fine when it heated up to around 175-180* after sitting for a few minutes.
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From: Turnin' Wrenches Infractions: 005
I'm starting to think it's the 160* t-stat. I did a little bit of research on t-stat's, and it seems a 180* or stock one is actually better for LSX motors, otherwise it may be too cool to properly burn all the fuel. So, maybe that's my issue, since it was fine when it heated up to around 175-180* after sitting for a few minutes.
A data logging tool might help. I bought the 'scan only' version of efilive, great to look at problems like this. I have it set up to log & graph about 16 things at once: air temp, coolant temp, rpm, throttle position, injector duty cycle, long term fuel trim, O2 output, etc, etc.
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I do want to change the plugs. I don't like the ones in there. My buddy said I should put a hotter plug in the car, so we put TR4's in it, instead of TR5's. But, I've got a set of TR5's sitting in the backseat that I plan on putting in the car sometime this week anyways. So, I'm going to try that first. If that doesn't work, I'll probably switch to a 180* or stock t-stat to see if that works.
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160*. But, something doesn't seem right, because it seems like it runs colder than everyone else's that I've seen. The car never really gets over 165* or so on the highway. In stop and go traffic, it'll sometimes creep up around 170-175, but not really in the colder weather we're having now.
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From: Rio Hondo texas
I was having a similar problem in my ss. Tried different stuff and what I found was the harness that goes down the left side of the motor by the # 6 cylinder had been rubbing for a while and was grounding out the wires causing the motor
Similar problems. check these wires by unpluging cs,o2, s starter wires and pull harness up to engine to make it wasy to repair. At first glance from on top wires might seem fine, until you take them out you will know if they are seriously damaged. If they r damaged i suggust to soder them and heat shrink them and put new conduet as i did. know my harnst lasted more than a year befor they gave me problems I strongly suggest check them if u havent found the problem alredy, its worth the trouble...thanks rich.
Similar problems. check these wires by unpluging cs,o2, s starter wires and pull harness up to engine to make it wasy to repair. At first glance from on top wires might seem fine, until you take them out you will know if they are seriously damaged. If they r damaged i suggust to soder them and heat shrink them and put new conduet as i did. know my harnst lasted more than a year befor they gave me problems I strongly suggest check them if u havent found the problem alredy, its worth the trouble...thanks rich.
