This one has me stumped at the moment. One of my 92 Kensingtons is running very rich at idle and is pulling excessive vacuum. (Sorry i don't have an actual #) So much it is actually holding my BOV open at idle. I have checked for obvious restrictions in the intake. Intercooler and all piping are free of any blockage, air filter is off, and the turbo is spooling freely. If anyone has ideas or experienced this, please let me know. Thank you!
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Ya, sorry. One thing i don't have yet is a vacuum gauge. Boost gauge is positive only. The car: 8.5:1 2g pistons, everything else internal wise is stock (stock cams). EVO 3 ex mani, gt3076 turbo (internally gated),2g o2 housing, 3in downpipe-2.5in out, fmic with aluminum pipes, 2g maf, pte 680cc injectors, aeromotive fpr, ECU stage 3-chipped for maf and inj. Sorry i dont have a solid vacuum #. I switched over to my Synapse BOV wich has the boost port to hold the piston shut, but it still pulled open at idle. It will shut, naturally, as i increase rpm and vacuum drops but hesitates if i jump on it. I know i should recirc the BOV, but that's still not a reason for it to be open at idle or while i'm trying to accelerate. Tried to lean out at idle, but doesn't help. Still seems adding fuel with out enough air. I'll try to get a solid vacuum reading asap. Thanks.
Forgot to mention it ran fine for first few min and then started to surge and die out. MAF and BARO codes. But MAF checks out ok.
turbowop
Well-known member
As long as you're recirculating the BOV, it should be fine even if opening a little at idle.
*edit* I see that you are running it open atmosphere. You really need to recirculate it if you're running MAF based fuel metering. That "boost port" only helps to keep the BOV from leaking at WOT. It does nothing at idle or may even exacerbate the issue.
*edit* I see that you are running it open atmosphere. You really need to recirculate it if you're running MAF based fuel metering. That "boost port" only helps to keep the BOV from leaking at WOT. It does nothing at idle or may even exacerbate the issue.
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Ah better.
+1 to Wop, recirc the BOV.
You mentioned leaning the idle AF, how are you doing this? Did not see an SAFC or related device in your list.
How did you wire up the 2g MAF? The MAF may check out good but the codes are basically saying no signal to the ECU.
Is the issue better or worse when the car is warm vs cold? MAF codes could keep the ECU out of Closed Loop operation and make it run funky ( depends on how good the chip is matched to the entire setup ).
Also do you have logging capabilities? It would tell you/us a lot more like fuel trims, O/C loop status, coolant temp, etc. All these have contributed to symptoms like yours.
+1 to Wop, recirc the BOV.
You mentioned leaning the idle AF, how are you doing this? Did not see an SAFC or related device in your list.
How did you wire up the 2g MAF? The MAF may check out good but the codes are basically saying no signal to the ECU.
Is the issue better or worse when the car is warm vs cold? MAF codes could keep the ECU out of Closed Loop operation and make it run funky ( depends on how good the chip is matched to the entire setup ).
Also do you have logging capabilities? It would tell you/us a lot more like fuel trims, O/C loop status, coolant temp, etc. All these have contributed to symptoms like yours.
Quoting realtimedrivline:
Forgot to mention it ran fine for first few min and then started to surge and die out. MAF and BARO codes. But MAF checks out ok.
The only thing that both the Karman section and the BARO section of the MAS have in common is the SENSORS GROUND from pin #24 of the ECU to the MAS. You either have it wired wrong or a bad connection.
Forgot to mention it ran fine for first few min and then started to surge and die out. MAF and BARO codes. But MAF checks out ok.
The only thing that both the Karman section and the BARO section of the MAS have in common is the SENSORS GROUND from pin #24 of the ECU to the MAS. You either have it wired wrong or a bad connection.
fivestardsm
Well-known member
We double checked the connections in the plug and actually meter traced the wires from the ecu plug to the maf plug to make sure that we had the correct G/Y wire. Where would the ground for the #24 pin be located (termination end), or were you refering to a ground on the ecu board itself that comes off from a common ground?
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Muskrat
Well-known member
ECU Wiring
Pin 24 IS the ground wire for those sensors. Make sure it has continuity across the wire (pin on connector to pin on ecu connector) and from that pin (on the ECU) to the ECU ground pin. Also check to make sure the pin on the wire is making good contact with the pin on the ECU.
Do you have the factory service manual? I'd go through the harness diagnostic for both of those sensors, just to be sure.
Pin 24 IS the ground wire for those sensors. Make sure it has continuity across the wire (pin on connector to pin on ecu connector) and from that pin (on the ECU) to the ECU ground pin. Also check to make sure the pin on the wire is making good contact with the pin on the ECU.
Do you have the factory service manual? I'd go through the harness diagnostic for both of those sensors, just to be sure.
