Restricted revs - intermittent

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Yoshi
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Re: Restricted revs - intermittent

Postby Yoshi » Tue Aug 26, 2014 2:52 pm

Eh. that's more an idle concern. As long as it doesn't die, all good!

congrats btw.
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Re: Restricted revs - intermittent

Postby Terry » Sat Aug 30, 2014 5:02 am

Thanks... I suggest kids to everyone, especially mine for the right price :)
I experienced the 3500 restrictions (note: not sure if this is accurate with the swap) for the first time cruising down the highway for about 5 minutes and then it went away... stayed the same when playing around with the gears and clutch. I would let off the gas, put it on and it would hit 3500 like a brick wall, so i'm thinking I'll clean the MAf, check the Crank Sensor ohms (right?)
And I was mistaken about the fuel pressure gauge - l got an oil pressure one installed, and if it matters, that kept steady at 60 psi.
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Re: Restricted revs - intermittent

Postby M20_fever » Sat Aug 30, 2014 6:40 pm

test the tps too.
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Re: Restricted revs - intermittent

Postby Terry » Wed Sep 24, 2014 3:36 am

Today I got around to starting somewhat on a diagnosis. I tried a different DME and added another engine ground, and cleaned the other grounds. Still the same problem.
I'll check the values on the CPS and TPS.
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Re: Restricted revs - intermittent

Postby Terry » Tue Sep 30, 2014 4:24 am

Both the cps and tps tested out fine using the bentley manual steps.
The next thing to test would be the MAF I suppose. It says in the manual that the car goes into limp mode when there is a fault in the maf. What is this limp mode like? Anything like what I described, about getting a pretty sharp cut off at 3500 rpm, however still being able to rev above, but at a much slower rate?
I guess I'll drive it with the MAF unplugged to see.
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Re: Restricted revs - intermittent

Postby Yoshi » Tue Sep 30, 2014 10:30 am

Limp mode? Shit, when my maf is unplugged, the car won't even move. It'll just barely idle if at all.
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Re: Restricted revs - intermittent

Postby M20_fever » Tue Sep 30, 2014 2:19 pm

I had the same symptoms with my m20 when the AFM was bad, but it was all the time not intermittent.
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Re: Restricted revs - intermittent

Postby Terry » Wed Oct 01, 2014 3:53 am

Shouldn't something like this throw a code? I did the stomp test and got the 1444 all good reading.
BTW, pretty sure that when this does happen, it only happens at WOT, and then only sometimes.
Keep coming back to the Crank Pos. Sensor on many posts of the same type... none of posters actually went to the trouble of testing the sensor though, just guesswork. Could the CPS have readings within spec and still go bad ocassionally? One thing I didn't check was the distance it's mounted from the sprocket wheel...
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Re: Restricted revs - intermittent

Postby Yoshi » Wed Oct 01, 2014 11:11 am

E30 ecus are fuuuucking stupid. They only toss a code if shits really bad or it's an O2 sensor (ha!). The CPS might test out right but it might pick up noise if the shielding has been compromised. If you ever cracked open a TPS and looked at it, you'd wonder how it functioned for more than 2 weeks. It's like this brush mother fucker that literally sweeps across a metal contact area.

Though, I'm not saying TPS, but I'm saying TPS... Sadly, I have like 3 lying around.
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Re: Restricted revs - intermittent

Postby Terry » Thu Oct 02, 2014 9:47 pm

Well, I have another TPS and MAF to swap in one at a time to see if that does it.
Mechanic says that the CPS was new.
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Re: Restricted revs - intermittent

Postby Yoshi » Fri Oct 03, 2014 11:09 am

You looked at it. Did the CPS LOOK new? Even then, "new" doesn't mean "works" but I just like double checking previous mechanics' work.
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