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Do I need a map sensor?! Bogging issue @3k rpm


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yeah i know i really didnt think getting a 95 would screw me like this is seems like an oddball year because the 96 and ups ecu's are different same with 94 and prior. fortunately enough i was able to get a pdf file of the entire car and some help with a nice wiring digram from dans performance parts! guess i just need to get a scope and see the digital output of my speed sensor. plus new ngk coil wires will be here tomorrow so hopefully those help.

 

 

aslo when the throttle closes it was a nice grumble/ (backfire or afterfire, not sure of proper terminology) as it sounds freakin awesome i really believe it shouldn't be doing that.. any input?

 

the o2 sensors on the live data sometimes go to .03 .01 volts they sit at that voltage for awhile and sometimes will go back to normal then back to the standard range from .1~.9  The o2 sensor is a: LSH 24 bosch

Edited by Sube Buggy
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well i grounded the pin for the neutral switch and put a different type of speed sensor on (NPN 5 volt receives signal every time a cv bolt asses under the NPN sensor on the old vw trans) and it works on the scanner and seems fairly accurate to what my actual speed is. now the car still sputters and lags when i accelerate.. i figure the p0500 code would toss it into limp mode and that was my problem. what frig else would do that?! my fuel pressure is fine, i have new coil wires and spark plug both ngk (recommended on this topic) the plug wires did dim down the crappy idle at stop lights. the coil pack seems to be the original DIAMOND coil pack. the only other code i did have was a p1702 and the fact my o2 sensor monitor NEVER completes how long does it usually take. 

 

Is my car still in limp mode?! it sputters about 2.5k rpm but on my 4 speed trans first gear doesnt really have a problem until 4k + rpm and second third and fourth sputter around 2.5k rpm

 

Could it be my timing belt? i just put one on but all the marks lined up and the proper amount of teeth between the cam and crankshaft was there for both sides i think 40.5  and 44 or something in that ball park i know it was right when i set it up but what would happen if it was 1 tooth off? yes i did use a new tensioner as well the kit was from "Gates" the more i read it seems to have similar symptoms to skipping 1 tooth The most it possibly could look off is about half a tooth but when i lined everything up it was perfect so i dont know if it is possible to be off by half a tooth 

 

dont know if this helps now when i start it up it starts and runs like complete garbage, spews white smoke out the tail pipe for about 3 seconds thens stops and then about 5-10 seconds it idles totally normal like nothing happened... my coolant levels are fine too they have not dropped 

Edited by Sube Buggy
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the only other code i did have was a p1702 and the fact my o2 sensor monitor NEVER completes how long does it usually take.

 

once everything is at normal operating temp, this should complete - if it isnt, it could very well be keeping you in limp mode...

I am no expert by any means, but the O2 not functioning correctly is suspect to me...

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once everything is at normal operating temp, this should complete - if it isnt, it could very well be keeping you in limp mode...

I am no expert by any means, but the O2 not functioning correctly is suspect to me...

the o2 monitor not complelting would keep it in limp mode? maybe ill have to test it out. alot of the times the time the voltage is at .02 or .06 and i know it should be around .1 to .9 depending if it richens or leans the mixture out. and its a bosch not a standard OEM so milage is unknown. 

 

any idea on the white smoke on start up?? 

 

the car actually seems to run really lean when its stationary and after warming up. The spark plugs are new and the tips are white. its generally at 10.4 area and stays there when cruising which i hear between -10 and +10 isnt bad 

Edited by Sube Buggy
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Also it seems a lot of people have similar problems as me but it ended up being their maf sensor there was a guy that assumed his was okay since it died when he pulled the plug on it and it tested okay but he replaced everything else beside that and it DID end up being that. Any one have anything similar to this??

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i personally have not had any MAF problems that a shot of MAF cleaner didnt resolve, so I am not much help there. =P sorry

 

I have had an O2 sensor go, and yeah, it did bog the engine down when traveling at highway speed... lost a lot of power...

 

If you have access to another MAF, it would be worth giving it a shot, but honestly, I cant say for sure one way or the other.

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I appreciate the help a lot heartless! But is there any specific test I should aim for or any readings voltage wise? Any links on test would be awesome! And I might check out my fuel injectors and o rings in the rails cause I think my o rings are pretty shot

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for O2, the CEL code was all i had for diagnostics, that and the car running like crapola. :unsure: a new O2 (i believe it was denso) and it was back to running great again.

 

that jdmfsm link above should have any testing procedures & specs you should need... might take a little digging to find the right pages (main sections are labeled decently, but the smaller sections/pages are not - i will poke around a bit & see what I can come up with as well)

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thanks heartless i'm going to be checking out those oxygen sensors. I was digging around the car yesterday and figured out there was a bad idle along with taking off my pod filter. I bought a adapter and gasket where the four bolt holes are right before the MAF. i took off the pod filter and it idled like crap almost as if it had a turbulence issue.. could this be a suspect? i also suspect there is a vacuum leak around the injector seats since i reused the old ones so it could have smashed on so it would partially block or let air seep through. I know stupid me for reusing those o- ring seats..  <_<  <_< I was gonna use my cousins smoke machine he uses for halloween since they probably work just as good as ones made specifically to find vacuum leaks. I wont be able to check that out for another week since i'm going to Alabama for a music festival here soon. I almost feel as if the MAF is my culprit for making it run lean during hesitation my spark plugs are new and have frosted white tips. I'm assuming these airpod filter adapters are junk but i didn't think it would make the car idle worse since the i took just the filter off. heres what it looks like. 5RN176.jpg

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we tried putting one of those cone type air filters on our dodge truck... ended up putting the stock air cleaner set up back on it... it ran ok, but didn't sound quite right... aside from that, I have no experience with that sort of thing.

 

a quick check for sucking air around the injector o-rings - try spraying a little ether or carb cleaner in the general location... if the idle changes right away you know you have a problem and about where it is located.

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yeah its odd i doubt it would cause this much trouble ill giv that a try and also i tested the voltage and i came back with this. not sure if this should be what its supposed to be but:            (I thought pin 2 ((red and yellow on mine)) was supposed to be a 5 volt reference??) 

 

pin 1: battery voltage 13~14volts 

pin 2: ecu 5v reference (red and yellow pin 25 on b84 plug for ecu) no voltage positive voltage. when taken to positive battery terminal the voltage was that of the battery so is there a possible short? 

Pin 3: ground (Black/Red) 13~14 Volts 

Pin 4: Signal for ECU (White and shielded) 1 volt @750 rpm & 1.85 volts @3,000 rpm (this is all taken from idle in neutral) 

 

I also forgot to mention when i start the car without the MAF on the car it still runs fairly normal, just surges like it will die but never does 

Edited by Sube Buggy
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Ok, so I was right the MAP is only for the a/t cars. Codes for that combined with the P1702 means you used the harness out of an auto trans car. You need to put an extra ground pin in the ECU connector to switch it to manual trans mode. I think it's pin 50, but compare the pinouts of the a/t vs m/t ECU connector and find where the extra ground is. Do that and a lot of your issues may resolve themselves.

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pulled a pin i didnt need for pin 50 and grounded for the "manual transmission mode"  the car drives alot better but bogs a little bit still but now when i come to a stop it dies 50 percent at the time which it never did before. before it acted like it was going to die but never did and now it dies after i put in a pin and grounded it also pin 78 (blue /red ) or ( light green/ Black) i grounded as well it connects to the neutral position switch. i dont actually have the "switch" if that makes a difference. 

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  • 5 weeks later...
  • 2 weeks later...

Still havnt figured out the neutral switch it was only come up when I plug the two green connectors in (p1101) if nothing works out in the next couple months I might just say screw it and buy a stinger standalone and a harness for the ej22 until I can get an ej205 since I would already have a stinger, I don't want to sell it since I can for see how much fun this can potentially have not running like crap, it's pretty fun right now and it runs like crap between 2500 and 3500 don't know why it lets me go above that, I thought limp mode only lets you hit a certain point and that's all you can get up too. For example like 3k rpm. Also it has a grumble, popping sound backfire. Long term fuel trim was about 8.6 while short term is 21 or so seems a bit lean to me the long term doesn't seem terrible though

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