Sube Buggy Posted April 27, 2016 Share Posted April 27, 2016 hello guys I have a bogging issue that may or not be related to not having a map sensor. I took a 95 ej22 in a dune buggy with a vw trans. Dont know why but for some reason Subaru made this obd2 my car bogs at around 3000 rpm like some one is cutting out the fuel so it sputters. it idles perfectly through high neutral revs and it drives wonderfully up to 3k rpm (while driving only) once it hits 3rd gear it bogs around 2500 not sure the mph. I can go at a higher rpm but it sputters its way up there though. I did not keep the MAP sensor a lot of the swaps said nothing about it so kinda unsure if i missed something on that i'm finally starting to get codes to pop up. I have p0105 which is for the map (didn't install with swap) could this be my reason i'm bogging. fuel pressure is perfect at idle but not sure when driving the guage is inline between the filter and block. I have the up stream o2 sensor installed but not the second (Assuming it monitors catalyst efficiency). the vehicle speed sensor was a pain too, i figured this was the original culprit? I have small cars hall effect sensor kit thats designed to make the ecu happy i get a steady 4.23 volts when driving i feel like the ecu wants to see between 0 and 5 volts just not 4 please correct me if i'm wrong any issue on the epidemic would be greatly appreciated. thank you more than anything Ill attempt to make a video on youtube of it bogging tomorrow Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted April 27, 2016 Share Posted April 27, 2016 yeah - MAP sensor is gonna be critical. either the car is in 'limp mode' without it - or the A:F ratio is too far out to run. Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 27, 2016 Author Share Posted April 27, 2016 interesting even with the 95's? I see some people there car runs fine with the code mean while some say it doesnt but their symptoms are not similar.Im really curious why no one has mentioned the map sensor in these swaps, maybe the obd1 blocks dont need it as bad?? now its time to go to a junk yard and find a wiring schematic.. and a vacuum diagram. If i can figure out why this bogs this rail buggy will drive perfectly. Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted April 27, 2016 Share Posted April 27, 2016 well, I CERTAINLY am no expert. maybe some ECUs are fine because they revert to a base map that is 'close enough' ? hopefully, someone will chime in with 'swap' experience. If not, try checking at NASIOC. Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 27, 2016 Author Share Posted April 27, 2016 yeah i hope so too but i really appreciate the help though texan. but it seems like the ecu use the map as a secondary log for air flow (if i'm not saying that right sorry) like the MAF sensor inline with the intake is the primary source. Also i don't know why it takes so long for the oxygen and catalyst monitor to run when i have no catalyst... and it should be throwing more codes than one since i'm missing half my systems lol Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted April 27, 2016 Share Posted April 27, 2016 that lack of additional codes may be another symptom of 'limp mode' but it's just a guess on my part. most 95s were already OBDII I think. even though it wasn't required until 96. Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 27, 2016 Author Share Posted April 27, 2016 well that makes sense ive been trying to find info on what my era subaru does when it goes into limp mode but just came up with a bunch of stuff for newer wrx's sti's do you have an idea? i know theyre similar but what should i look for? Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted April 27, 2016 Share Posted April 27, 2016 (edited) I'm not sure - I know 'limp mode' on the turbos cut the boost. maybe it limits rpm on the na models? VSS will cause problems but, seems like you already have this bypassed? guesswork again. can you scan the ecu for pending codes? Edited April 27, 2016 by 1 Lucky Texan Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 27, 2016 Author Share Posted April 27, 2016 all i have is a crappy scanner that only reads codes that are already available ill barrow a buddy's scan tool. but i don't know if i bypassed it it has voltage but it really doesn't fluctuate. thats why i'm stumped not sure if its the vss, the map, or a possible code that hasnt popped up so i guess ill drive it around alot today and see what happens Quote Link to comment Share on other sites More sharing options...
1 Lucky Texan Posted April 27, 2016 Share Posted April 27, 2016 try a new thread asking for help with a swapped engine - might get someone with experience to reply. Quote Link to comment Share on other sites More sharing options...
wtdash Posted April 27, 2016 Share Posted April 27, 2016 (edited) Hi, I'm w/LT - The lack of a MAP is going to likely cause 'limp' mode or @ least 'impaired function'. The '95 2.2 engine is very similar to the '90-'94 used in the OBD1 cars - other than the different TPS, EGR - on the Automatics, engine harness, and maybe a couple other things. But the '95 ECU is OBD2 and more 'picky'. ....and before you ask, the ECU and wiring harness connectors are different, so you can't easily swap it in....although on your buggy it may not be near as tough. This LINK is for the '90-'94 ECU codes and there is a code 45 for the 'Atmos. Sensor', which may be the MAP?? It shows that it 'Sets sensor to 760 mmHg' - I'm not sure what that is, but it sounds like a 'limp/fail-safe' mode. So, either OBD1 or 2 you need the MAP, IMHO. GL, TD Edited April 27, 2016 by wtdash Quote Link to comment Share on other sites More sharing options...
kamesama980 Posted April 27, 2016 Share Posted April 27, 2016 No idea on how the ECU will react to the lack of a MAP sensor but I'd expect that if it were limp mode, it'd be more night and day: works up to X throttle or RPM period. the point is to avoid misfires, damage, and minimize emissions. Spitting and sputtering means misfires which is kind of the opposite of gentle, safe, and low-emissions. I HAVE seen similar issues with ignition problems. My VW Bug had some issues when I got it (some, ha!) one of which was as it warmed up, it ran worse and worse: cutting out at high rpm/load then moderate, then it'd only idle, then nothing. New distributor and points replacement device did the trick (since then I heard a bad condensor could do the same thing). Another was my old toyota pickup: had issues that ended up being the plug wires: dry it ran fine but with condensing moisture it'd short the wires but only above a certain rpm/load. it'd run fine then, like someone hit a switch, it'd sputter and barely run (low rpm/throttle was ok, high rpm, low throttle was iffy, low rpm, high throttle was iffy, mid-high rpm with mid-high throttle was no-go) the issue is that higher combustion cylinder pressures are more resistant to arcing (and ignition) so a borderline cable might end up as a shorter path only under those conditions. Found it when I grabbed the distributor cap/wires to adjust timing when it was humid out. ZAP,ZAP,ZAP,ZAP....hmm guess I'll make a trip to the parts store as soon as I can feel my arm again. Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 27, 2016 Author Share Posted April 27, 2016 thanks for the help guys looks like ill be grabbing a map sensor at the junk yard tomorrow i kept all wires from the ecu so ill just have to figure out which ones go where and install it hopefully ill be able to find a diagram. ive been unlucky that everyone that does the swap have the 3 or 4 plug ecu's i have the big 96 pin grey rectangle. might as well grab some plugs while im at it too. im about to upload a video and hopefully itll help a little bit. Quote Link to comment Share on other sites More sharing options...
WoodsWagon Posted April 27, 2016 Share Posted April 27, 2016 I would doubt the MAP would do it. 95 is a MAF based fuel injection system and the MAP is for the a/t and evap. A over sensitive knock sensor sure will though. It pulls all the timing and the engine runs like a dog. Try unbolting the knock sensor and relocating it to the bracket the battery ground cable attaches to on top of the starter, or whatever remote but still grounded spot you have available on your swap. If it runs fine, then get a new knock sensor and follow the clocking and torque spec installation instructions to bolt it back in the right spot. A dieing coil or ignition module can do that too. Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 27, 2016 Author Share Posted April 27, 2016 ill do some more checking when i get home but here is the video listen between 30 and 40 seconds the other stuff is just driving. Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 28, 2016 Author Share Posted April 28, 2016 woods wagon couldnt i just ground the wire but what would it do if i relocated it would the vibration or movment of the car still possibly make it "sense a knock" since its still connected? Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 28, 2016 Share Posted April 28, 2016 95 doesn't care about the MAP sensor. Some 95s didn't even have it to begin with. Fuel problem gets my vote. Need to check pressure while it's being driven and having the problem. Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 28, 2016 Author Share Posted April 28, 2016 thats what i thought, but i knew a lot of cars the map sensor is critical so it kinda made me second guess myself but im going to bench test the coil for proper resistances and unfortunately wont be able to see the pressure since its raining but what should i look for the fuel pressure acting erratic, to spike, or to dip?? Quote Link to comment Share on other sites More sharing options...
kamesama980 Posted April 28, 2016 Share Posted April 28, 2016 When the MAP sensor's critical, it's critical all the time. That's certainly a misfire, not limp mode. Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 28, 2016 Author Share Posted April 28, 2016 then why does it only happen when its around 3k instead of all the way through the rpm band or at idle? and then im curious why no one else whos done the swap reported using one or have problems without one. Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 28, 2016 Author Share Posted April 28, 2016 at almost seems it happens at lower rp in higher gears and in first it really deosnt do it so it kinda seems almost like its related to speed too Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 30, 2016 Author Share Posted April 30, 2016 Well i got a map sensor and wired it up and really didnt make much of a difference cruising in 3rd was a little bit smoother other than that its the same i still have to wild a bung for the secondary o2, there is no misfires that come up on the scan tool or any codes that come up. i was driving it around town and still no codes the monitors for the o2 sensors never finish. Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 30, 2016 Share Posted April 30, 2016 Rear O2 sensor doesn't make any difference for fuel trim. It's just a check sensor for the catalyst. Can you watch the sensor data on your scanner? 1 Quote Link to comment Share on other sites More sharing options...
Sube Buggy Posted April 30, 2016 Author Share Posted April 30, 2016 (edited) yeah i can i just bought a 100 dollar one from az today it might be cheap but im just glad i can read live data. i also need to see what my fuel pressure is when i drive and how to the fuel pressure be? like go up with rpm, stay the same pressure, go down or what? also i guess there is a secondary speed sensor? should i be worried about that Edited April 30, 2016 by Sube Buggy Quote Link to comment Share on other sites More sharing options...
Fairtax4me Posted April 30, 2016 Share Posted April 30, 2016 (edited) Fuel pressure should be about 35 psi at idle. Should go up to 42-45 with the fuel pressure regulator vacuum hose disconnected. Driving should see 35 psi while cruising, should go up to around 42-45 when under heavy acceleration. If pressure doesn't go up when accelerating, or drops below 35psi, fuel pump could be going bad or there may be a restriction in the fuel supply line or filter. Yes there is a speed sensor on the trans and one in the instrument cluster. Instrument cluster sensor takes the 8 pulse signal from the trans and cuts it down to a 4 pulse signal that sts sent to the ECU. If the ECU gets an 8 pulse signal it will think you're good twice as fast as you really are and could engage the speed limiter. Should be able to see vehicle speed on your scanner. Edited April 30, 2016 by Fairtax4me Quote Link to comment Share on other sites More sharing options...
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