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DISCUSSION => Engine + Driveline => Topic started by: Jorgeconrico on October 10, 2009, 05:33:58 PM

Title: Help don't know what else to do
Post by: Jorgeconrico on October 10, 2009, 05:33:58 PM: Hey everyone-

Basically the problem I have is that my car won't rev any higher than 5500 rpms. The car revs past that (6800) when the car is warming up, but when the car gets hot the car seems to hit a "rev limiter" at 5500 and won't go any higher. If I shut the car down for 10 -20 min its fine and I can take to the redline, but then the problem continues. I thought the problem was resolved but i put new control arms and CABs on so I was beating on the car a bit today and of course it spoiled my day.

When the problem first started I took care of the "mess under the intake", changed the plugs and fuel filter. BTW I'm not pulling any codes with the stomp test. Any help would be awesome:)
Title: Help don't know what else to do
Post by: Jorgeconrico on October 11, 2009, 05:32:27 AM: Beat on the car some more and another stomp test revealed a code of 1244 which I believe is the camshaft sensor, guess i'll be buying a new one... Has anyone had trouble with these symptoms which were related to the camshaft sensor?
Title: Help don't know what else to do
Post by: RED IS 91 on October 11, 2009, 05:48:43 AM: Test your sensor first to see if it's within specs.

The crank sensor is 650+- and the cam sensor is 1250+- .The bentley manual is incorrect. Test between terminals 1 and 2 on your cam sensor and see what Ohms you have .

(http://i141.photobucket.com/albums/r73/bogeyman700/cps.jpg)
Title: Help don't know what else to do
Post by: Jorgeconrico on October 11, 2009, 07:55:42 AM: I'm not getting any resistance. I'll be ordering one today. Thanks a million.
Title: Help don't know what else to do
Post by: Jorgeconrico on October 17, 2009, 10:35:39 AM: I installed the new sensor, but I'm still not getting a reading. The multimeter is not faulty. I'm out of ideas...:confused::confused:
Title: Help don't know what else to do
Post by: RED IS 91 on October 17, 2009, 12:34:51 PM: You hooked a multi meter up to a new sensor and you didn't get a reading??

Either your testing it incorrectly or you've got your meter on the wrong setting?
Title: Help don't know what else to do
Post by: Jorgeconrico on October 17, 2009, 01:07:49 PM: I'm testing on terminals one and two and the multimeter is set to ohms.
Title: Help don't know what else to do
Post by: DesktopDave on October 17, 2009, 03:05:50 PM: I was going to guess cam sensor myself, it controls spark timing. That could cause what you're seeing now.

But you have to get at least some resistance on the cam sensor... can you ohm out something else like a speaker or light bulb to verify your meter?
Title: Help don't know what else to do
Post by: Jorgeconrico on October 17, 2009, 03:32:35 PM: The meter is fine. Red IS 91 was right, it was on the wrong setting. Anyway, there is resistance, but the problem now is that I'm seeing oil on the cam sensor. Could this be causing the problem? Does oil seep in the hole which the sensor is located as the car gets warmer, thus causing the high rpm misfires?

The only other thing I can think of is the O2 sensor. I have no idea when it was last changed, if at all.
Title: Help don't know what else to do
Post by: DesktopDave on October 17, 2009, 03:54:29 PM: Make sure that resistance is in spec. It has to be very close or the DME will ignore the sensor. Oil shouldn't do much by itself, unless it's collecting rust & metal flakes. Then it'll keep things from running right.

Maybe do another resistance test on the sensor when it's warm? You have a spare right now anyway, test the original when it's hot & replace if it's bad.
Title: Help don't know what else to do
Post by: Jorgeconrico on October 17, 2009, 04:59:08 PM: I just tested it while warm and I got a reading of 1541 Ohms. Do you think the oil is providing the extra resistance, which is causing the high reading?
Title: Help don't know what else to do
Post by: DesktopDave on October 17, 2009, 08:49:54 PM: Could be. I've never taken one apart. They're just a coil...reverse of an electromagnet. That's why the resistance is so critical. I just had a thought...is there a gap spec for the sensor? Or does it just bolt in?
Title: Help don't know what else to do
Post by: Jorgeconrico on October 17, 2009, 09:03:10 PM: Yes, I think RED IS 91 posted a page from the bentley manual at the beginning of the thread, which lists the gap spec, but I'm not certain.
Title: Help don't know what else to do
Post by: RED IS 91 on October 18, 2009, 04:42:08 AM: Test your old sensor to see what the resistance was with it ?
Title: Help don't know what else to do
Post by: Jorgeconrico on October 18, 2009, 07:10:16 AM: Its dead. I'm just going to say hell with it and buy a COP kit to see if it fixes the problem, but seriously I hope the oil covering isn't the problem, because wouldn't I then have to open up the timing case and change some gaskets??
Title: Help don't know what else to do
Post by: KenC on October 18, 2009, 09:54:04 AM: The sensor goes into the timing case... it's going to get oil on it.
Title: Help don't know what else to do
Post by: Jorgeconrico on October 18, 2009, 05:38:51 PM: Ok, I didn't know if that was normal. Guess I'll try to get a new COP kit to see if that cures the misfires. Thanks everyone.
Title: Help don't know what else to do
Post by: DesktopDave on October 18, 2009, 05:45:55 PM: Did you check your DME coolant sensor? There are two, one for the dash cluster & one for the DME.

If it's not telling the DME that your car is warmed up you'll stay in open loop and the timing would remain dialed back. That might cause your symptoms. You'd also see poor gas mileage & maybe a little black smoke at WOT.
Title: Help don't know what else to do
Post by: Jorgeconrico on October 18, 2009, 06:32:26 PM: I'm not seeing poor gas mileage or black smoke. Sorry to ask this but how would I test these sensors to get a diagnosis? I need to stop being lazy and download the bentley manual.
Title: Help don't know what else to do
Post by: Jorgeconrico on November 04, 2009, 04:20:37 PM: Ok, just tested the crankshaft sensor for fun and it read about 500 ohms. Is this low enough for it to be a problem or is it within reasonable range?

Edit: reading 492 Ohms
Title: Help don't know what else to do
Post by: Jorgeconrico on November 04, 2009, 08:15:18 PM: Sorry to keep posting, but i was doing some testing and found out that the original CAM sensor, which is off the car was perfectly fine reading 1250 Ohms exactly. The new CAM sensor which is currently on the car is reading 1420 Ohms (it is also a cheap aftermarket brand, Facet). I'm not really sure where to go from here. I guess I will be putting the old one back on and see what happens. I'm just unsure why the hell the resistance is high especially if the part is new. I also don't understand why I was getting a 1244 code for a cam sensor when apparently it was fine to begin with. This problem is really annoying. Like it says in the first post, its as if the engine is hitting a "false" rev limiter. I've done some further research and some people say this is caused by camshaft sensors, others say crank sensors. I've even read a COP kit may cure it. I don't want to drop anymore $$ until I know what to replace. If anyone can give some input if they have had this problem I will give you my first born son.
Title: Help don't know what else to do
Post by: quinn11m20 on November 04, 2009, 09:06:19 PM: Hey this may sound way out of range, but have you tried to change your computer chip?
Do you know anyone with the same car nearby? It sounds like a long shot I know. But try it. All you will do is emphasize that its not the chip. Kinda of guarantee.
Title: Help don't know what else to do
Post by: Jorgeconrico on November 04, 2009, 09:17:07 PM: No I don't know anyone near me, but i recently purchased a chip and it was doing this long before I got it. I wouldn't be against putting the stock chip back in just to see, but I really don't know if it will help. Thanks though.

Put the original cam sensor back in and its reading a perfect 1250 Ohms.....:o
After testing the crankshaft sensor I'm wondering if that could be the problem. Like I said before only reading 492 Ohms.:confused::confused:
Title: Help don't know what else to do
Post by: AcSchnitzer318is on November 05, 2009, 08:05:42 AM: If you haven't replaced the crank sensor, that would be my only other guess.
Title: Help don't know what else to do
Post by: Jorgeconrico on November 05, 2009, 08:11:39 AM: Thanks for the reply, but before I go and drop like 160 bucks, I just wanted to know if the reading I got (492 Ohms) is within spec (650 Ohms). I know its low but I don't know if its low enough to be a problem. Anyone out there test theirs recently??

Edit: I looked at the bavauto thread that Red IS 91 posted and I am in the ballpark with 492 Ohms. Wonder why the two base numbers are different 650 v 540 Ohms. Thanks for posting that thread.
Title: Help don't know what else to do
Post by: DesktopDave on November 10, 2009, 07:42:16 AM: Did you check the gap too? A perfectly good sensor will miss if it's too far away from the trigger wheel. I'm just guessing, but at high revs maybe the cam pos sensor is losing sync, then resetting & topping off your red line at 5k?