engine wont rev over 3000 RPM

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chulse1492
Posts: 8
Joined: Wed Apr 19, 2006 1:33 am
Car: 1993 infiniti Q45
1995 Land Rover Dico
2003 Suzuki Katana
Location: Vancouver, Washington

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OK so it seems I fix one problem and another pops up. So a little back round first. The engine has 10hours run time on it. Everything is pretty much brand new or reman. The issue is when driving when it hits 3000 RPM its like it hit a REV limiter. when in park again like it hit a REV limiter. When starting it take longer then it should to start (about 5sec of crank). When starting from a light sometimes it will die, sometimes it will sound like it about to die (Like its REALLY bogged down). When It just sits idling every once and a while I can hear the thump of a miss.

Other than that, she runs pretty good.
Could it be a misaligned sensor, or a bad sensor.
Also so It out there and know what has been done. It's time using method B, Idle air screw is set at about 5 turns out from all they way in. The TPS is showing 0.4 Volt closed. If i check the right wires that is. (can someone confirm the wires I need to tap in to for this.) And the last thing, She is throwing a check engine code 11. I'm guessing the code is coming from start not the run cycle. since the code is the as soon as the key is turn to the "on" position
Any help would be great!! :confused:

Chris
***Update*** could this be caused by low fuel pressure (fuel pump going bad, or clog fuel filter)?
The fuel pump is humming something fierce ***update***

PS Sorry if this sound confusing but I havent slept since Sunday morning. Really trying to get this car dialed in.


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AZhitman
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Location: Surprise, Arizona
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Hey Chris!

Definitely the fuel pump is an issue - Replace it soon, or you'll be replacing the fuel pump controller as well (more expensive).

The 3K limit sounds almost like limp mode, but shouldn't be the case on a car of that age. I'll get the Q experts in here for you - For the time being, get some rest, and if you don't already have it, here's the FSM for your car:

http://www.nicoclub.com/FSM/Q45/1993.pdf (R-click and save to your PC)

chulse1492
Posts: 8
Joined: Wed Apr 19, 2006 1:33 am
Car: 1993 infiniti Q45
1995 Land Rover Dico
2003 Suzuki Katana
Location: Vancouver, Washington

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Thank you AZHitman! I have a hard copy of the FSM (it's seen better days pretty messed up now). I been wanting a PDF version. dont have to haul that big a** book around now. You rock :dblthumb:

So back to the question at hand. As I stated in my first post, I get a code 11 on the check engine light. per pages EF &EC-80,81, and 82 I have gone though the diagnostic steps and everything checked OK. When checking the component (pages EF & EC-202) everything again was within spec. However when rotating the CKPS the voltage only fluctuated between 0V and 2.68V. Is this OK. Never saw anything close to 5V. Also as I rotated the CKPS I could hear the injectors functioning. So that tells my that the ECU is getting a signal from the CKPS.

So my question is
Is the ECU getting the right signal? And if it is could there be a stored code in it that would cause it to start in limp mode?
Also,
How do you effectively erase stored codes?

I wait to bask in the knowledge that is NICO! :bowrofl:
Thanks
Chris

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elwesso
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Car: 94 Infiniti Q45t 5 spd
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You could have 2 problems here. If the fuel pump is humming loudly, then you need to replace that. IT may or may not be causing your issues, but I have seen a bad fuel pump do stuff like this.

It really sounds more like you're in limp mode from the CAS. The CAS don't typically fail however I've seen a couple. More likely the connector might need cleaned, or you bend the pins a little bit to get a better connection.

IThaJ0kaI
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Car: 96 G50, 90 S13 hatch
Location: Port Richey, FL

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Mass air sensor? They will make a 3000rpm limiter.

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elwesso
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IThaJ0kaI wrote:Mass air sensor? They will make a 3000rpm limiter.
He said he's getting a code 11 in the posts, which is for the CAS. If the car is going into limp-mode it would have to be throwing a code.

chulse1492
Posts: 8
Joined: Wed Apr 19, 2006 1:33 am
Car: 1993 infiniti Q45
1995 Land Rover Dico
2003 Suzuki Katana
Location: Vancouver, Washington

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Spot on Wes. Dirty connector on the CAS. She purrs now. and code is gone.
Thanks guys
Time to party!!
:thewave: :domo: :taz: :monkey: :banana: :woot: :lock: :BnB: :band: :badger

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AZhitman
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Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 S13, 92 SE-R, 92 Silvia Qs, 98 S14.
Location: Surprise, Arizona
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I <3 it when we can be helpful!

WELL DONE WES!!!!!

THis makes all the hard work and late nights worthwhile. Wes, remind me to give you a raise. ;)

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elwesso
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Just another day, man.

It still boggles my mind why people continue to drive these cars... :D

Zer0_KooL
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Joined: Sat Jul 21, 2012 10:51 am
Car: 1995 Infiniti Q45 (G50)
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elwesso wrote:Just another day, man.

It still boggles my mind why people continue to drive these cars... :D
Probably the same reason women stay with wife beaters :chuckle:


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