'91 Sammy runs rough

[Jim Blackwood]

Hey guys, good to be here. I have a '91 Sammy that is mostly stock, better bumpers and tires and a short top is about it. Pretty rusty but I use it on my 5 acres to run between the house and the shop, pick up dead limbs, pull the sand drag on the driveway, etc. It's a fine little buggy for my needs.

Recently it's begun running rough (fresh plugs sometimes helps a little) so I took off the TPS and sprayed fader lube into it and put it back and for a day or so it was perfect then started acting up again. BUT, it idles just fine and from what I've read that doesn't sound like a bad TPS.

It does have an engine light and I do have a scanner, but I haven't figured out how to hook it up to the sammy to read codes.

OK, that's about it, y'all can pile on now.

Jim

[fixkick]

Hey guys, good to be here. I have a '91 Sammy that is mostly stock, better bumpers and tires and a short top is about it. Pretty rusty but I use it on my 5 acres to run between the house and the shop, pick up dead limbs, pull the sand drag on the driveway, etc. It's a fine little buggy for my needs.

Recently it's begun running rough (fresh plugs sometimes helps a little) so I took off the TPS and sprayed fader lube into it and put it back and for a day or so it was perfect then started acting up again. BUT, it idles just fine and from what I've read that doesn't sound like a bad TPS.

It does have an engine light and I do have a scanner, but I haven't figured out how to hook it up to the sammy to read codes.

OK, that's about it, y'all can pile on now.

Jim

hello and welcome;'  (TBI throttle body injected SammI)
CEL lamp glowing they go to limphome mode and run rich and foul spark plugs.

the   ECU is OBD1 , no scan tools fit it , sold in stores, yes the GM Tech1 scan tool can scan  this OBD1, but is rare to find now. and connects to  ALDL SDL SERIAL PORT.
but does have   DlcL jack , jumper to get CEL flash code from 12 to 53 or sow. 12 = no codes set)
here is the simple wiring this year,  see ecu pin A3 blue/yell,.  jumpered to ground is DIAG blink out mode

http://fixkick.com/sammi-stuff/late-sammi-efi-94.jpg

suzuki  loves to move the DLC<to 3 or 4places under the hood,just for fun and for Hiroshima.(grin)

DCL= diagnostic logic connector,
it many look like the Vitara 91
jump  B TO C,   paperclip unbent, metal  only clips






The 1989-95 1.6L TFI and MFI engines use a diagnostic monitor coupler, which is located in the engine compartment near the battery
THE WIRE COLOR IS KEY TO FIND ing this connector,  on new car had rubber cap. DLC>

[Jim Blackwood]

Thanks for the assist. Things have changed some. The '91 Sammy now has a 1.6L 8v engine complete with intake and TBI and a Sidekick ECM (94-95 Sidekick Track 2-Door MT ECU ecm PCM Engine Computer 33920-56B50) to run it with the extra wire installed to the noise suppressor. Sammy exhaust manifold, no cat. full exhaust with stock tailpipe. I removed the EGR temp sensor and plugged the hole with a bolt because I wasn't able to find a connector to plug it into.

It runs good except it has a code 51 and rich idle. I found the temp sensor connects to ECM pin A17 and signal return, if I connect this is it likely to clear the code? (can the connector be had from any source?) Thanks.

Jim

[fixkick]

Topic FrankenKicks. (where any things is possible under the hood) I love em , fun to get them happy sure.
code 51 is EGR Dead.
and 51 is done 3 or more ways 1989 to 2004 sidekicks
and not the same CALIF or FED ecu.
the EGR thermo sensors is a CALIF first car used, then copied by Suzuki to the 1995 year so not unique to CALIF and in 1996 they went to EGR MAP way.
a17, ? ECU pin (EGRT)

I have the full ECU lists of all p/n used by suzuki and GOE both, in the sidekick forum under ECU pdf

B50 is it. sub code
here it is, my work

https://fixkick.com/ECU/EPC-ECU96-98/all...9-95NA.pdf

looking now to see what that is.
you do know I have the ECU EGRGT bypass resistor trick right>? >
is that ECU outside USA???????? you in Georgia?


no it is not a B50 ECU it is a 1995 B51,
the label in ebay if fuzzy , and hard to read by me but is a B51. or B5x, with x being upgrades to base like ECU) the upgrades are a secret never told.

B51 , 8v, manual trans. Federal model not CALIF.
okay , A17 8v is IAT sensor intake air temps. just put back the sensor
A17 uses special ECU sensed ground A24 pin
and in fact seen here all those facts off main ECU pages
https://fixkick.com/ECU/8v-tbi-schematic91to95.jpg

EGR temp sensor is pin a16
and a dummy resistor there makes ECU thinks it is happy. 10,000 ohms any watts.
as seen here
http://fixkick.com/EGR-H3LL.html

run with O2 sensor unplugged, so it can run right if does the 02 sensor is stuck at 0vdc, causing huge rich misfire
is the injector stock?
do both injector pins pulse, and not 1 hacked to make it run as seen by hackers.?
8v uses a dual transistor driver to both pins if one is dead hacker hot wire the pin and not runs rich forever.
both pins TBI injector must pulse I have scope photos of both if needed.




IAT error is a totally other code
called
DTC code 23
per DTC page
here

http://fixkick.com/ECU/DTC-errors/DTC-jtgh.html



the EGR valve is 100% useless with the CAT missing
the EGR modulator is dead with CAT missing, because there is no more CAT backpressure to make it work at all.
so 10,000 ohm it.
when the EGR opens the EGRT gets roasting hot and reads 10k ohms and code 51 passes. the sensor real is just a thermister.

I call 02 problems , wrong injector, well lots rereally
1: o2 dead stuck at 0vdc
2: fuel pressure too high for sure at idle if super rich at idle.
3: Map failing or VAC to it ,connected wrong.
4: injector tip leaks when it is closed.
5: injector o-rings leak all the time key on.
6:ECT sensor is dead or the wrong one put there, the ones sold for EUROPE can never work, ebay hell there.
ECT is super easy to test on my ECT page. in pan of hot water, and ohm meter (DMM)
7": thermostat missing/ bad or wrong one or those silly fail safe kind now stuck in fail safe mode FOR EVER.(stuck open for ever)

that is all I can think of in seconds.

[fixkick]

sorry Im so slow, email updates here are dead.
and I do want to help you any way I can
Happy Eclipses 1:30 pm,

[Jim Blackwood]

Almost got to see the Halo... not quite though, still was a very small sliver of light creeping around the edge. Worth trying though. 3.09 pm here. I am in Florence, KY.

Identity of ECM: I can't say if it's really a B50 or a B51, I suppose if it makes a difference I could pull the board and get the numbers off it, could you identify it by that method?

Your schematic is a better match for the wiring in my '91 Samurai, not that this makes it correct. But you show a red/green wire on A16 for the EGR temp sensor which matches the '91-'95 1.3L diagram I have. (The schematic I was using showed it at A17.) I do not think I have that wire. Is the A connector the yellow one? I have to identify the pin 16 location but there are a few open holes. Do you have a wire with the attached pin connector? I'll need to make sure it goes in the right spot.

Resistor fix: I would have no problem with hooking that in at the ECM, even internally if it eliminates the EGR error, and then I could just remove the EGR stuff. If I understand your resistor fix then you basically just jumper the air temp sensor input to the EGR input? Again, identifying the connection points is critical but I have no problem with circuit board repair.

I think my sensors are in good shape, I've replaced both of the temp sensors. Idle rich condition is not extreme, sometimes rich on initial startup (have to flood clear to start usually when warm) and an intermittent rich miss at idle. Injector is stock and wires to it have not been abused.

I can go down your list of things to check but I'd like to clear the code 51 first. Is it possible that could clear up the idle? Could be an instant win.

Jim

[Jim Blackwood]

Here is a shot of the case tag. B50
Also a shot of the board number, might be able to verify with that.

   

   

Soldering a 10k resistor to the connector pins would be child's play and fortunately the pins are clearly numbered on the board.

So. a 10K resistor between A16 and A17 then? Is that the trick to eliminate the EGR error code 51?

Thanks,

Jim

[fixkick]

Here is a shot of the case tag. B50
Also a shot of the board number, might be able to verify with that.


Soldering a 10k resistor to the connector pins would be child's play and fortunately the pins are clearly numbered on the board.

So. a 10K resistor between A16 and A17 then? Is that the trick to eliminate the EGR error code 51?

Thanks,

Jim

yes,  if the harness is gone so is the EGRT connector
the hack here is simple, the ECU
some newer ECU set code 53 that means if powered on scan it sees the EGRT missing, (infinity ohms)
the early ECU many do not do this test, I think also that is  CALIF test. code 53.
51 is a  live engine running test. (hot engine and never at idle)
but is DUMB as a brick.
it fails to do the real 2 test test. and does only the 1 test. (I call it the expectation test)
In 1996 they do test A and B, and is mandated by EPA law to do so. but not here.

It expect the EGR to be flowing now, test. At cruise .
and if is reading about 10,000 ohms it sees that magic current flow as at spec, EGR is good.

yes,  this is how it works see on my EGR page

some cars around this year, use the MAIN MAP sensor vacuum drop test. and had no EGRT at all. my 91 had this and up to 1993 maybe.
some cars have used EGR main using wrong EGR valve and the new owner does not know that  this car does not need the EGRT at all,  
seeing the EGRT there is not any proof at all after 30 years. (swaps happen)
only the ECu matters.!

and there is no way to fool the , MAP sensor drop test. at all. (aside from a custom complex processor box to fool it, with a dynamic vac leaking device)

your ecu is 94/95.
not sure if it is MAP test  or EGRT version,  I do not  know. (I guess EGRT)
using the resistor there will prove it.

i think yours is EGRT ECU.  using the thermo sensor probe to prove it works. at cruise.
good luck

[Jim Blackwood]

Thanks but I'm still a little confused. Should I put the resistor between pin A16, EGT temp signal and the return A24? That would cause current to flow as if the temp sensor was there, right?

My '91 Samurai never had the EGRT, the new engine did and I'm just guessing this ECM expects to see it. It is marked as 10-8-95 FE Sidekick. But if wiring it this way gets rid of code 51 I'm good. I guess I can try that and see if it works. Does the code have to be cleared? How?

Thanks,
Jim

[Jim Blackwood]

OK, here we go: The attached photo shows the permanent fix of code 51 by soldering a 10k resister between pins 16 and 24 of the B50 ECU. The code 51 goes away and only code 12 (normal) remains, CEL stays off. The resistor is on the bottom side of the ECU board, so the board has to be removed from the case entirely to do this, simple, just 6 screws. No external wiring required, no EGR required, so far as I know. Off road modification. May be OK in some states and with some vehicles for street use, particularly as applied to engine swaps.

Feel free to use this photo however you like, just post my name with it. (Jim Blackwood)
   

The start and idle may have improved, still too early to say for certain but so far it seems better. I'll know more in a few days.

Jim