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OBD2 Connector by bomluuk
Started on: 11-03-2013 01:51 PM
Replies: 35 (1559 views)
Last post by: TbirdMarc on 01-15-2014 10:40 PM
bomluuk
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Report this Post11-03-2013 01:51 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
I've tooled around the archives for about 2 days and was not able to find information that I'm looking for. I'd like to connect an obd2 to my swap (1998 3800 s/c in a 1986 GT with 5 speed) so I am able to connect my obd2 diagnostic tool. Is there a diagram or pinout for this?
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Report this Post11-03-2013 01:59 PM Click Here to See the Profile for FIEROFLYERSend a Private Message to FIEROFLYEREdit/Delete MessageReply w/QuoteDirect Link to This Post
Very simple for the OBD II connector pin 2 goes to PCM usually pin 59 of C1, pins 4 and 5 are ground and pin 16 is battery + 12 volts constant. the tan wire from PCM C1 pin 15 is not needed and any other wires on the connector can be removed. Dan
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bomluuk
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Report this Post11-04-2013 12:19 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thank you so much, Dan! I got my connector from a junkyard this morning, swapped the pins to the correct positions and will wire it up when I get home from work. Thanks again!
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bomluuk
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Report this Post11-05-2013 11:47 AM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Worked great and I got my code. P0452 - Fuel Tank Pessure Sensor Circuit Low Voltage. After looking around a bit I have come to the conclusion that I should not be getting this code at all. I did not have my PCM reprogrammed because I was under the impression that I did not need it done with the 5 speed tranny. Am I correct in those two conclusions?
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Tweeder
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Report this Post11-05-2013 01:25 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
I got that same code after my 3800sc and 300 lph swap, I just tuned it out so it wouldn't pop up again. Not sure why it came up.

------------------
86 SE Convertible 3800sc 4t65e HD.

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bomluuk
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Report this Post11-05-2013 02:02 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Did you have any issues with your motor prior to getting it tuned out?
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bomluuk
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Report this Post11-08-2013 04:10 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
I'm looking into my vacuum system to see if I can find a solution to my problem. I'm getting diagnostic P0452 - Fuel Tank Pessure Sensor Circuit Low Voltage. My engine runs and idles fine. The issue is that when I get on the throttle, there is hesitation to accelerate. It stutters or stumbles, those are the two words I can use to describe it. Is there anything wrong with how I have my vacuum lines connected? My other question would be concerning the evap switch (if you notice on my diagram, it is not connected to anything. I don't know where it is or what it looks like). Is that located on top of the fiero's evap canister? If not, where is it located?

The image below is what how I currently have my vacuum connected.


The image below is what I have been using as my guides (both of which I found here on Pennock's, not mine)
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FieroJimmy
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Report this Post11-08-2013 06:33 PM Click Here to See the Profile for FieroJimmySend a Private Message to FieroJimmyEdit/Delete MessageReply w/QuoteDirect Link to This Post
Did you add an FTP sensor when you swapped the engine? The Fiero doesn't have one stock.

The newer pcms use it to monitor evaporative emissions system functionality. Normally it'll be a small three wire sensor attached to the top of the fuel pump module.
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bomluuk
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Report this Post11-08-2013 07:01 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
To the best of my knowledge, I did not install an FTP sensor. I don't remember doing anything to the fuel tank except for the fuel lines.
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phonedawgz
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Report this Post11-09-2013 01:38 PM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
Most people have that programmed out of their PCM. Much simpler than trying to make the evap controls work on a car that doesn't have them.
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bomluuk
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Report this Post11-09-2013 01:49 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
I was under the impression that with a manual trans that I wouldn't need a pcm tune. Am I wrong? It worked perfectly in the 88 fiero my setup came out of.
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Report this Post11-09-2013 06:12 PM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well if you don't care that your MIL light is on all the time I suppose you don't need to have the PCM properly programmed.
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bomluuk
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Report this Post11-09-2013 06:20 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Ok. Thanks. So does this not have anything to do with the stutter issue?
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phonedawgz
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Report this Post11-09-2013 06:32 PM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
Nope - Did you look at a dirty MAF for your studder issue?

The MAF measures air flow. it does this by measuring how much current is needed to pass through a wire to keep it at a constant temperature. Using a over oiled foam filter or even just over time the MAF wires can get coated with crud. That crud insulates the wires. So when you pop the throttle open the insulated wire doesn't read the quickly changing air flow. The PCM doesn't inject the correct amount of fuel right away and a hesitation is the result.

http://www.youtube.com/watch?v=xQGSkWEC_u4

With the 3800 you don't have to remove anything but the MAF itself



Harbor Freight sells bits to unscrew the MAF - http://www.harborfreight.co...y-bit-set-68457.html - $9.99
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bomluuk
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Report this Post11-09-2013 06:41 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have tried that but maybe I didn't spray enough cleaner on it. I'll give it another shot. Also, Scotty Kilmer videos are pretty sweet.
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bomluuk
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Report this Post11-11-2013 01:35 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Sprayed the MAF sensor pretty good with the MAF cleaner. No change Bought a fuel pressure gauge from harbor freight. I'm getting about 40 psi with the key on, but engine off. I get about 45 at idle and 50+ at rev, so that seems to be close to within spec. What else should I look for?
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phonedawgz
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Report this Post11-11-2013 09:15 PM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
I'm not sure what drugs Scotty Kilmer is on, but I want to make sure I don't ever do them.

So it could still be a bad MAF, it might have been nice to grab one from the junk yard if you had the chance, just for testing.

Did the 3800 always do this or is it something that just started?

Does the engine miss when it hesitates or just a hesitation?

You have a good connection to the MAP sensor, no kinks or other obstructions correct?

Plugs look good?

GM changed the MAF between 98 & 99. An -04 MAF is 96-98. An -05 MAF is 99+ Your PCM needs to be programmed correctly for your MAF. So if your MAF is 98 or earlyer it needs to be mated with a PCM programmed as such and vice versa. If you look at the MAF in my picture above you can see it is an -04 MAF

Disconnect and plug the hoses to your BBV and see if the trouble stays the same.

[This message has been edited by phonedawgz (edited 11-11-2013).]

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Report this Post11-12-2013 08:30 AM Click Here to See the Profile for FIEROFLYERSend a Private Message to FIEROFLYEREdit/Delete MessageReply w/QuoteDirect Link to This Post
With a manual tranny swap with the 3800 engine you need the PCM programmed to match for more then just the check engine light. the IAC code has to be altered for it to idle properly or even half decent wise and not want to stall most of the time on deceleration or idle. Dan
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bomluuk
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Report this Post11-12-2013 10:46 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Did the 3800 always do this or is it something that just started?

Here is the background on my setup. My father put this motor in his 88 GT 5 speed back around 2002-2003. Everything ran great with no issues and always put a smile on our faces. However, he couldn't get it registered in CA, so we decided to put it in my 86 GT 5 speed. Back then we experienced the exact same issue. We cut our losses and put the 2.8 back in so I would have something to drive for the little while before I left the country for a bit. The motor sat in his car's cradle from then until last year. I got it back from him and put it in my car and I have the same issue. So the engine has never run correctly in my car, but ran like a champ in my father's car.

 
quote
You have a good connection to the MAP sensor, no kinks or other obstructions correct?

Are you referring to vacuum line, electrical connector, or both? I checked the vacuum the other day with my finger gauge and there is vacuum.

 
quote
GM changed the MAF between 98 & 99. An -04 MAF is 96-98. An -05 MAF is 99+ Your PCM needs to be programmed correctly for your MAF. So if your MAF is 98 or earlyer it needs to be mated with a PCM programmed as such and vice versa. If you look at the MAF in my picture above you can see it is an -04 MAF

It is a-04 MAF on a 98 PCM.

 
quote

Does the engine miss when it hesitates or just a hesitation?
Disconnect and plug the hoses to your BBV and see if the trouble stays the same.

It feels like its missing. I'll try to get a video of it so you can have a better idea. I'll disconnect the BBV, probably tomorrow, and see what that produces.
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bomluuk
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Report this Post11-13-2013 07:00 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
There was no change when I disconnected the BBV.

Here is a little video I took. The audio quality isn't great, but the first rev depicts the issue I'm having.
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bomluuk
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Report this Post11-16-2013 11:20 AM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Shameful weekend bump. Gonna see if I can find a MAF at the junkyard today.
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Report this Post11-17-2013 12:17 AM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoEdit/Delete MessageReply w/QuoteDirect Link to This Post
obd2, pin 59 clear or blue ?
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bomluuk
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Report this Post11-17-2013 01:57 AM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
C1 is blue.
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bomluuk
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Report this Post11-17-2013 09:04 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
After a snowy day at the junkyard, to add insult to injury, was not able to find a MAF
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bomluuk
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Report this Post11-26-2013 03:01 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Unplugged the MAF sensor and the engine ran worse.
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phonedawgz
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Report this Post11-26-2013 08:14 PM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
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Report this Post11-27-2013 12:14 PM Click Here to See the Profile for Lou6t4gtoClick Here to Email Lou6t4gtoSend a Private Message to Lou6t4gtoEdit/Delete MessageReply w/QuoteDirect Link to This Post
SO, WITH A 97 3800sc FROM A RIVIERA, wired as 1998 per gmtuners, and using a 1998 ecm, What # MAF is needed ? Thanks
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phonedawgz
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Report this Post11-27-2013 03:37 PM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
AFH50M-04 96-98 Series II NA/SC - Part that fits into the throttle body is tubular - round

AFH50M-05 98+ Series II/III NA/SC until electric throttle body - Square 'dog whistle' looking MAF
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bomluuk
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Report this Post12-03-2013 08:53 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
I got a used MAF in the mail from eBay, installed it and am having the exact same problem. However, while under the decklid today, I found some things that I have questions about. Hopefully I can get this figured out, as I have to renew registration this month. Here goes...

Question 1:
What, if anything, gets connected here? The other side is connected to the back of the air filter box.


Question 2:
Where does this line, that I have traced in red, connect to on the other end (to the right)? Also, what is that under the air filter box?


Question 3:
What should the MAF reading be at idle? I'm getting about 35 cfm at 785 RPM, and 177 cfm at 3625 RPM.

Question 4:
What should vacuum pressure be at idle? I'm getting 23 in/Hg (11.3 psi) at 741 RPM.
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bomluuk
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Report this Post12-08-2013 08:05 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Harmless bump...
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Report this Post12-11-2013 09:39 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Desperation bump.
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Report this Post12-12-2013 10:10 AM Click Here to See the Profile for Midn1ght Driv3rClick Here to Email Midn1ght Driv3rSend a Private Message to Midn1ght Driv3rEdit/Delete MessageReply w/QuoteDirect Link to This Post
I don't know anything about maf/map sensors.

Your first question is the recall air tube. Nothing goes into it but it should be capped off.
Second question : that is the egr solenoid purge hose.
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Report this Post12-13-2013 02:03 AM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Midn1ght Driv3r:
Second question : that is the egr solenoid purge hose.

What is done with the egr solenoid purge hose, since there is no port on the 3800 egr solenoid?
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Report this Post12-17-2013 07:22 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
Evening bump...
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Report this Post01-14-2014 08:41 PM Click Here to See the Profile for bomluukSend a Private Message to bomluukEdit/Delete MessageReply w/QuoteDirect Link to This Post
I did some continuity checks on the MAF today. I found something that seems a little weird to me, so I'm gonna ask here and hopefully someone can tell me if its normal or not.

C1 and C2 are disconnected from the PCM, along with C203.
Pin 19 should be ignition Positive Voltage (hot in run) and connect to F of C203.
I metered from pin 19 on C1 (pink wire) to C+ on the MAF (pink wire) and got continuity, seems normal.
The part that I'm wondering about is that I also got continuity with ground.
Is this wrong?
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Report this Post01-15-2014 10:40 PM Click Here to See the Profile for TbirdMarcClick Here to visit TbirdMarc's HomePageClick Here to Email TbirdMarcSend a Private Message to TbirdMarcEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by bomluuk:

I did some continuity checks on the MAF today. I found something that seems a little weird to me, so I'm gonna ask here and hopefully someone can tell me if its normal or not.

C1 and C2 are disconnected from the PCM, along with C203.
Pin 19 should be ignition Positive Voltage (hot in run) and connect to F of C203.
I metered from pin 19 on C1 (pink wire) to C+ on the MAF (pink wire) and got continuity, seems normal.
The part that I'm wondering about is that I also got continuity with ground.
Is this wrong?


Should be ok because you are reading the maf resistance to ground. You should try adding a few extra grounds from your engine to frame. I know I seen some info about that here.

[This message has been edited by TbirdMarc (edited 01-15-2014).]

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