Vandergriff84 Posted May 1, 2013 Share Posted May 1, 2013 Ok, So here is my problem that at this point I have yet to encounter onther RB owner who has also had. My motor runs great, but I have yet to get it to idle under 800 RPM. Most of the time it idles around 900 according to my timing light. My autometer tach usually says a 100 or so more. My concern is that I can't propperly set the timing unless it idles at 650 as the FSM says. When I check the advancement with the light it reads between 5 and 10 degrees with the CAS turned all the way to the right. If I turn it all the way to the left it reads like -5 to -10 degrees and has a very difficult time running. I do not know if these reading are correct for this RPM. I would assume that the CAS should let me adjust between 0 and 30 degrees. Now for the idle problem, I have been through everything that causes the usual idle problems and nothing seems to be out of order. I have no vacuum leaks, TPS is set at .47V, I have 3 MAF's no change among them, I have new O2 sensor, I have two IAC units and I have cleaned and tried both no change, I have set the Idle screw all the way in and 900 is as low as it goes. The one thing that is bugging me that I can not for the life of me figure out is why I have this whistling sound coming from around the IAC on the intake. When I pinch the pcv hose the whistle goes away but as soon as I rev the engine it comes back. I have a greddy style intake and a motorsport shop in my town says that I would need a stand alone ecu or some sort of tuned ecu to work with it. I would love to hear what you guys have experienced in this regard and any input toward helping me resolve my idle problem would be greatly appreciated. Quote Link to comment Share on other sites More sharing options...
ZT-R Posted May 2, 2013 Share Posted May 2, 2013 Have you checked it with propane or a fogging machine? Stock cams? Quote Link to comment Share on other sites More sharing options...
cheftrd Posted May 3, 2013 Share Posted May 3, 2013 Unplug the IAC and see what happens. If it dies, or the idle drops way down, that means there's probably a control issue. Sounds like you may have a vacuum leak, though. Your timing issue sounds goofy, as well. Standing in front of the engine, turning the CAS clock-wise will retard the timing, and counter-clock will advance it. Even at 900 rpm, turning it all the way counter will send it deep into BTDC, like 30+ degrees. Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 3, 2013 Author Share Posted May 3, 2013 So I don't know anything about propane or a fogging machine. What does that do? I do have stock cams for the only non stock items on the motor are the greddy style intake and greddy BOV. I have recently learned that the BOV has to be circulated back into the intake side of the turbo to keep the engine from stalling when I let off the gas. Its amazing how many people have told me that it didn't matter. I know that I have unplugged the IAC before and I think it droped slitely but not very much. As for the timing I ment to say clock-wise retard and counter-clock advance, I was thinking about which way the screws moved in the slot. But yeah when I advance it all the way i get to maybe 10 degrees and if I retard all the way I get way below zero. Could it be that the timing belt is off a tooth or something? I have not removed the belt so I would think it would be on there correct. Quote Link to comment Share on other sites More sharing options...
cheftrd Posted May 3, 2013 Share Posted May 3, 2013 Smoke or fogging machine puts smoke into the intake tract to find leaks. Propane is used around the intake to find leaks also. If you find a leak, it'll speed up the engine. This method has "risks"...LOL. If you unplug the IAC and there's very little change, then you have an air leak somewhere behind the throttle(s). Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 3, 2013 Author Share Posted May 3, 2013 Ok, I did some messing around this evening and this is the new info I have. I adjusted my throttle plate stop back to where the plate starts to stick so that I know the plate is fully closed. I then re-adjusted the idle and I got it down to 700. I was still hearing the whistle so I started looking for it. When I pinched the PCV hose it would go away so I disconnected it and plugged both sides and the whistle was gone. So I checked the RPMs again and it was down to like 630. I am going to look for a new PCV valve tonight. Does anyone know which one to buy? I checked the timing again and it is still sitting at +5 degrees with the CAS fully advanced. I am thinking that the belt must have slipped a tooth or have been installed incorrectly. If anyone has any input on this that would be awesome. Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 4, 2013 Author Share Posted May 4, 2013 Ok, So I checked my timing at TDC and all three marks line up so the only thing I can think of now is that the ECU is retarding the the timing for some reason but I do not understand why it would do that or what else could cause it to do so. I am still looking for a new PCV. I have not found a cross refference for it yet. Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 4, 2013 Share Posted May 4, 2013 Check your knock sensor operation , only thing i can think of . ECM will retard timing if knock sensor detects detonation ( or loud engine noise ) . Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 4, 2013 Author Share Posted May 4, 2013 I put a new pcv valve in today and the whistling sound is gone. It is now idling at around 650. The problem is that it is still retarding the timing and it won't stay running if I rev it and I mean if I give it just a little bit of gas and let off it dies. If I am not mistaken that is usually a sign of air leak but to this day I still can't find any. Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 4, 2013 Author Share Posted May 4, 2013 Check your knock sensor operation , only thing i can think of . ECM will retard timing if knock sensor detects detonation ( or loud engine noise ) . How do I go about checking the knock sensors? Is there anything other than detonation that would cause the knock sensor to send a bad signal? Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 4, 2013 Share Posted May 4, 2013 Mechanical noise that is close enough to it , will . Vac. leak will give it a high idle or surge . You adjusted the throttle stop , maybe you went too far . Check your TPS reading at idle to see if it's within spec. Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 4, 2013 Author Share Posted May 4, 2013 Mechanical noise that is close enough to it , will . Vac. leak will give it a high idle or surge . You adjusted the throttle stop , maybe you went too far . Check your TPS reading at idle to see if it's within spec. Ok so would the noise throw a code? I have checked the TPS and it is spot on. Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 4, 2013 Share Posted May 4, 2013 I haven't seen one set DTC for noise . Have seen change in timing , especially Chevy Cavalier when timing chain is bad ( makes noise ) . If knock sensor is bad ( open or short ckt ) , it will set code for sensor . Some ECM will go into failsafe/conservative mode ( less timing ) . Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 6, 2013 Author Share Posted May 6, 2013 I am getting no codes for knock sensors so I am leaning towards the idea that it is still some sort of air problem. When I spray carb cleaner at the back of the intake flange the motor sort of boggs down and idles real rough for a seccond and the goes right back to the way it was. Some one told me that if it does anything when you spray carb cleaner there and not any where else then there has to be a leak. So I am going to take the intake off tomorrow and replace the gasket hope that it fixes my problems. Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 8, 2013 Author Share Posted May 8, 2013 Ok I fixed the flange problem but everything else is the same. The timing is still way retarded and it wont drop back to idle when I rev it. At this point I can't do any thing until I can find a consult to show me more of what the ECU is doing and what it is seeing. I am hoping I can find a Nissan expert in the area to take a look at it cuz I am just about spent on this thing. Quote Link to comment Share on other sites More sharing options...
ZT-R Posted May 8, 2013 Share Posted May 8, 2013 On a side note how strong is your battery, and how is your engine grounded? Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 8, 2013 Share Posted May 8, 2013 If you have an OBD 2 connector ( should have one if it's a 96 or newer ) , i might be able to get come PIDs . Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 10, 2013 Author Share Posted May 10, 2013 On a side note how strong is your battery, and how is your engine grounded? The battery is plenty strong and the engine is grounded strait to the battery. Quote Link to comment Share on other sites More sharing options...
Vandergriff84 Posted May 10, 2013 Author Share Posted May 10, 2013 If you have an OBD 2 connector ( should have one if it's a 96 or newer ) , i might be able to get come PIDs . I only have the Nissan consult connector. PIDs? Quote Link to comment Share on other sites More sharing options...
Domzs Posted May 10, 2013 Share Posted May 10, 2013 I only have the Nissan consult connector. PIDs? Parameter IDs , data that you see on the scanner . Quote Link to comment Share on other sites More sharing options...
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