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D17VTECPOWER threads consolidated - how a member should not behave
Re: Do I need a camber kit?
Was the alignment shop able to align it back to factory spec? When I was dropped 1.5” I needed one in the rear to bring it back to factory specs. Negative camber is not a bad thing and it can help with dialing in the handling as you want. I gave my alignment shop the exact front and rear settings I want and they set it. I had adjustable arms in the rear and bolts in the front though.
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Re: High RPM on the highway
Changing the transmission isn’t a big deal, I have an extra. But if the transmission was in 3rd gear when the PCM wants it in 4th gear, wouldn’t the PCM set a code by now? I drove it a couple hundred miles with this problem so far, so I would think it would have a code by now. The lack of codes makes me think that the PCM is keeping the trans in 3rd gear for some reason. As far as I know, the trans is either in the gear the PCM wants it in, or it sets a code.
Last edited by D17VTECPOWER; Feb 21, 2018 at 11:21 AM.
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Rep Power: 118 Re: Do I need a camber kit?
Was the alignment shop able to align it back to factory spec? When I was dropped 1.5” I needed one in the rear to bring it back to factory specs. Negative camber is not a bad thing and it can help with dialing in the handling as you want. I gave my alignment shop the exact front and rear settings I want and they set it. I had adjustable arms in the rear and bolts in the front though.
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Rep Power: 118 Re: High RPM on the highway
Have you ever seen something this consistent and severe not set a code in a modern vehicle with OBD2? I know that these cars will set trans codes because the transmission in my 2004 Civic briefly slipped once when it was very low on fluid, and it set a P0730 code instantly, and the D4 light started flashing. So I know that these cars can set trans codes for very minor problems.
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Re: High RPM on the highway
So I know that these cars can set trans codes for very minor problems.
What could make the PCM think it shouldn't upshift to high gear? Where's your TPS voltage at? What about ECT?
What about trans data list, did you look yet?
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Rep Power: 118 Re: High RPM on the highway
I guess the PCM can ignore major issues then. Also, I s it OK to run the engine at 4000 RPM on the highway, or will it cause problems besides using more gas? The TPS reads 9 percent at idle and 92 percent at full throttle, which is normal. I didn’t check voltage yet. The coolant temp reads between 180 and 195, depending on conditions, which is also normal for this car. I’ll see if I can get trans data when I get back home. What else could make the PCM not upshift?
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The PCM only detects what the engineers programmed it to detect.
Check data DURING a problem event.
What did a vacuum modulator do on old cars?
The TPS reads 9 percent at idle and 92 percent at full throttle, which is normal. I didn’t check voltage yet. The coolant temp reads between 180 and 195, depending on conditions, which is also normal for this car.
What else could make the PCM not upshift?
Wait, let me rephrase that whole thing. Think about what normal shifting is controlled by........RPM, throttle position, temperatures.... LOAD. Is there a major LOAD sensor input that is skewed, erroneous, inaccurate? (MAP high?)
Wouldn't a poorly running engine require extra throttle to maintain a given amount of power output? If the computer seen a bunch of throttle open input (and corresponding manifold vacuum drop) it's gonna think it needs to keep the RPM high because you're wanting extra power.......so it won't upshift or may upshift very late. Meanwhile you've only been flooring it because the engine has no power....
Not saying that's what is going on, just stuff to think about--how and why.
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Rep Power: 118 Re: High RPM on the highway
The PCM only detects what the engineers programmed it to detect.
Check data DURING a problem event.
What did a vacuum modulator do on old cars?
Wait, let me rephrase that whole thing. Think about what normal shifting is controlled by........RPM, throttle position, temperatures.... LOAD. Is there a major LOAD sensor input that is skewed, erroneous, inaccurate? (MAP high?)
Wouldn't a poorly running engine require extra throttle to maintain a given amount of power output? If the computer seen a bunch of throttle open input (and corresponding manifold vacuum drop) it's gonna think it needs to keep the RPM high because you're wanting extra power.......so it won't upshift or may upshift very late. Meanwhile you've only been flooring it because the engine has no power....
Not saying that's what is going on, just stuff to think about--how and why.
Computer: GIGO
Check data DURING a problem event.
What did a vacuum modulator do on old cars?
Wait, let me rephrase that whole thing. Think about what normal shifting is controlled by........RPM, throttle position, temperatures.... LOAD. Is there a major LOAD sensor input that is skewed, erroneous, inaccurate? (MAP high?)
Wouldn't a poorly running engine require extra throttle to maintain a given amount of power output? If the computer seen a bunch of throttle open input (and corresponding manifold vacuum drop) it's gonna think it needs to keep the RPM high because you're wanting extra power.......so it won't upshift or may upshift very late. Meanwhile you've only been flooring it because the engine has no power....
Not saying that's what is going on, just stuff to think about--how and why.
Computer: GIGO
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Rep Power: 118 Re: Do I need a camber kit?
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Rep Power: 118 Re: High RPM on the highway
Yes, but the MAP readings hasn't changed since the transmission issue started, and I am not sure if the 1.1 volts I measured was accurate, since the POS multimeter I used to check the voltage died a couple days later.
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...From a standing start, floor it and don't let off the gas pedal....... and let it try to shift at redline in every gear.....If it flares between gears or slips in a gear it should show itself
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Rep Power: 118 Re: Rubber vs. poly bushings- A durability experiment
The results are in! I am having trouble getting the pictures to upload, so I need to figure that out. However, the rubber bushing got very mushy and sticky, and the polyurethane bushing was unaffected. Like I said, I’ll try to get the pictures to upload.
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Rep Power: 118 Re: High RPM on the highway
If you do go past redline and hit rev limit then you know it’s a bad tranny, if it shifts there hopefully is only a bad sensor input.
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Rep Power: 118 Re: High RPM on the highway
Just thinking even if the PCM is thinking your under too much load to shift while in third, it has no choice but to shift at redline.
If you do go past redline and hit rev limit then you know it’s a bad tranny, if it shifts there hopefully is only a bad sensor input.
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Rep Power: 118 Will driving without power steering damage the rack?
I don’t have power steering on my 2005 Civic. I took the system out 3 years ago when the pump died, and I don’t mind not having power steering. However, I heard that the rack will be damaged by not having power steering because way more force Is required to steer the car, and I also heard that the rack can be damaged if you drive without fluid in it. Is any of this true? Thanks.
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Rep Power: 118 Re: High RPM on the highway
UPDATE- If I reset the PCM by disconnecting the battery, the transmission shifts fine for about 5 minutes. After that, it downshifts to 3rd gear and won't upshift to 4th gear unless I reset it again. What does this mean?
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Got fault codes, maybe try a different code reader?
If you think it's a pcm problem.....Swap PCM (and immobilizer) from your other car as a test?
If you think it's a pcm problem.....Swap PCM (and immobilizer) from your other car as a test?
