93 DOHC in 87 Fiero. My A/C request turns on the FAN but does not engage the clutch. I tried to put two 10K resistors between pin C and pins A and B, but I do not think that 2.5Volts is the right value. could someone tell me the voltage on pin C of the A/C pressure transducer when the A/C is operating correctly? Thanks
I own page 12!!
Can anybody answer this poor pathetic souls question? He needs all the help he can get. (Formulamoe, you are a thread killer)
I am pathetic. My A/C pump has now let all the magic oil out. Sinister Performance just sent me my chip back reprogramed and I am going to have to beat on the car for a while and see how it holds up!
Well all started out good today, I finished installing the exhaust, remounted the starter, attached all battery and ground cables, attached battery, turn key. And wait for it, wait for it, let suspense build. You guessed it, nothing happended, and i do mean nothing. I didn't get an inkling of juice to the front. No lights, no fuel pump hum, nothing. So I check the battery. 13.09 volts. check my grounds, all good. check voltage at the back of the allternator (to verify power to the starter) 13.07 volts. double check all connections again. turn key nothing. check connection from battery to the black junction block next to the battery. good connection. Where do I look next??? thanks for any info or insight.
Well all started out good today, I finished installing the exhaust, remounted the starter, attached all battery and ground cables, attached battery, turn key. And wait for it, wait for it, let suspense build. You guessed it, nothing happended, and i do mean nothing. I didn't get an inkling of juice to the front. No lights, no fuel pump hum, nothing. So I check the battery. 13.09 volts. check my grounds, all good. check voltage at the back of the allternator (to verify power to the starter) 13.07 volts. double check all connections again. turn key nothing. check connection from battery to the black junction block next to the battery. good connection. Where do I look next??? thanks for any info or insight.
dan
Are you getting juice to the fuse box?? If not then its probably a fusible link
Three wires supply power to the ECM, The two orange wires supply constant power, and the pink/black wire supplies switched power on ignition. Then you need at least one good ground. I would take a meter to the orange wires to make sure they both have power to them. Then make sure you have power to the pink/black wire when the ignition is on. This pink/black wire also goes through the C203 connector. If you get power at all three, and have a good ground, the check engine light should work, and your fuel pump relay should activate for three seconds, otherwise you have a computer problem, or really messed up wiring.
Wnet out early this am, hoping the magical electrical fairies cam and fixed the problem. no luck.
These orange wires are connected to the black coneector in the back (by the battery). The one on the right is attached via a pole, the orange one on the left just ends with the black connector. tested for voltage at this connector, was 13.09.
Next I moved inside to the black/white connector where I found to be a pink wire w/black stripe. tested for voltage there, 0.00 volts, ran wire back to connection just b4 bulkhead, still 0.00 volts.
I believe this to be the wire that goes to the fuse box, I may be wrong. Mechanical grmlins I was ready for, electrical will drive me insane. Will it make a difference if I haven't had the chip modded yet. thanks again for advice and input
dan
[This message has been edited by bonaduce (edited 11-04-2007).]
did some more testing since last post. found a beige wire w/white stripe in white connector, showing .05 volts. traced pink w/black (pink) back into computer. Attached my meter to pin and 0.00 volts. Decided to run a jumper wire to the pink w/black terminal, after I hooked all connections back together, and wahla, I have dash lights, turn the key, and pop, no more lights. I haven't changed the fuses around like eric suggested, when I got my harness, so I figured some fuses would pop. However, I still have no fuel pump hum, and as stated b4 no dash lights again.
more wiring checking, after studying the pinouts from darth's site, I decided to check D17 (orange wire) for constant pcm power. nothing found. another orange wire at D21 or D22 shows no power either. Calling it a night, have to get ready for the game. stay tuned for updates. advice/comments appreciated.
Ok, well, we're getting somewhere with what you have done. Basically you have confirmed that you can backfeed power to the car via the ECM power wire, not the safest thing to do, (I think you tried to activate the starter solenoid through a 18 gage wire, and a 5 amp fuse... Not a good idea!) but it means something. First, I must place a disclamer, Custom harnesses are not all the same, but usually follow the origional manufacturer's color code, and basic layout Which I assume is very simular to the stock V6 in order to be more plug and play friendly. So your electrical problems are most likley going to be the same as any V6 Fiero. That being said, This is what you want to see... This is your stock harness already on the car near the battery, there is the C-500 and a pigtail with a pair of fuseable links that supply all the power to the car, (lights, horn, radio... everything!) This must be connected to the power junction block near the battery. There is a red wire that comes off of the battery positive terminal that ABSOLUTLY MUST also be connected to this power junction block! Without this wire, your car has NO power. Also, you should have something like this going to the junction block: The big wire is inside the engine harness, and connects the alternator to the power junction block. This is where the smaller plug with the fuseable link comes into play. This plug supplies power to this connector This wire is supposed to supply two of the orange wires on the ecm with there constant 12V, which holds the memory in the ECM, as well as operates the ECM. Without this wire connected, your ECM is dead, it won't do anything without power here.
The pink/Black wire to the ECM that goes through the C203 only tells the ECM to turn on which should cause the Check engine light and the fuel pump relay to both kick on. It gets its power through a fuse in the fuse box, then through the ignition switch in the steering column. The fuse box gets its power directly from the red wires with there fuseable links in the first picture. Hopefully this will guide your search a little more clearly, knowing the proper path of power flow. Also, You had better check your fuses one more time, I am betting you fried one of them with that little test you did before.
[This message has been edited by Fierobsessed (edited 11-05-2007).]
Dan, have you checked your fuse box for power? It sounds like you are not getting juice to it which should indicate a bad fusible link. One the junction box by the C500 connnector that feeds youre electrical systems, make sure the metal strip at the oppositie end of the heavy gauge red wire that goes to your starter main terminal that has a larger hole and smaller hole, fits on to the bigger and smaller posts and are seated fully and secured with the appropriate nuts.
This is your stock harness already on the car near the battery, there is the C-500 and a pigtail with a pair of fuseable links that supply all the power to the car, (lights, horn, radio... everything!) This must be connected to the power junction block near the battery. There is a red wire that comes off of the battery positive terminal that ABSOLUTLY MUST also be connected to this power junction block! Without this wire, your car has NO power.
Dan, if the power junction terminal metal jumper checks out as mentioned, check those two fusible links in the pics as they supply the power to your ECM, coilpacks, starter soleniod
thanks for the info guys, am at work now will start digging into everything when i get home. thanks for those pics fieroobsessed. that one with the black connector on it is not hooked into anything yet. thats what i get for looming b4 installation, looks like i missed a connection
Update: well got home and pulled the loom off to look for the connection in the above picture (fierobsessed, 2nd pic posted). No connection inside the wiring harness.
next: checked for voltage after these two wires after the fusible link, no voltage, then checked voltage b4 fusible link, no voltage
next: moved to the fuse box, and found that there is no voltage there, what a suprise.
which still leaves me with this connection that has to go somewhere
dan
[This message has been edited by bonaduce (edited 11-05-2007).]
Update: well got home and pulled the loom off to look for the connection in the above picture (fierobsessed, 2nd pic posted). No connection inside the wiring harness.
next: checked for voltage after these two wires after the fusible link, no voltage, then checked voltage b4 fusible link, no voltage
next: moved to the fuse box, and found that there is no voltage there, what a suprise.
which still leaves me with this connection that has to go somewhere
dan
disregard that connector ..it is not used, go ahead and clip it off if you want. I just left it there in case you wanted a fused power supply for perhaps a nitrous system or something ..the 2 fusible links must be connected to the power junction box or you will not get power to the rest of the car. There is a heavy gauge red wire in the harness that goes to the main postive terminal on the starter ..the other end of that wire terminates at the power junction box and it has a metal 2 hole ring type terminal connector. Note the terminal connector in the picture
That must be secure on the junction box. The smaller terminal is were the ring connectors on the fusible links go. Note the ring connectors in the picture
I am assuming you also have the positive battery lead hooked up to the starter main terminal as well
[This message has been edited by Erik (edited 11-05-2007).]
Oh, I see, you used the Stud on the starter to feed the power back to the power junction block. Normally the Fiero's Positive battery terminal has a smaller but still fairly heavy gage wire that bolts to the junction block to feed the rest of the car. Makes sense now.
well got home from work today, and decided to test the fusible links for continuity, took a bit of left handedness to do it but both checked good. So I decided to check for voltage again, still no volts. So I figure I would call it a night, no voltage coming out of the c500 connector, I'll just grab another from the yard this weekend. As I am getting ready to leave the garage, I do'nt know why, but something didn't seem right. So I decided to check for voltage again, but this time by the post, as I jammed the test lead into the top post my radio and headlights popped up, good thing my son left the key in the on position. Long story short, the nut that held on the ring for the fusible links was under the other connections, when I tightend the nut for the wiring harness it pulled the top part of the connector off the nut,(look at pics 1 and 2) causing no feed. Removed nut, wire brushed EVERYTHING, reinstalled, power to the dash. next stop, lets see if this pig runs. Thanks for leading me in the right directions Eric and Fierobsessed.
well got home from work today, and decided to test the fusible links for continuity, took a bit of left handedness to do it but both checked good. So I decided to check for voltage again, still no volts. So I figure I would call it a night, no voltage coming out of the c500 connector, I'll just grab another from the yard this weekend. As I am getting ready to leave the garage, I do'nt know why, but something didn't seem right. So I decided to check for voltage again, but this time by the post, as I jammed the test lead into the top post my radio and headlights popped up, good thing my son left the key in the on position. Long story short, the nut that held on the ring for the fusible links was under the other connections, when I tightend the nut for the wiring harness it pulled the top part of the connector off the nut,(look at pics 1 and 2) causing no feed. Removed nut, wire brushed EVERYTHING, reinstalled, power to the dash. next stop, lets see if this pig runs. Thanks for leading me in the right directions Eric and Fierobsessed.
dan
Sweet glad to know you found the problem ..now get ready for excitement!
Here's some stuff I have been working on in solidworks:
A dogbone mount that should work for both the 91-95 and 96-97 intake manifolds and uses the engine lift bracket as well as the power steering eliminator bracket for support.
And an equal length tubular header 1.75 primary's
And a shorty style header:
Let me know what you guys think!
-Jeff
------------------ --180* t-stat, cams, 96-97 intake swap, FFP pulley, A/C Idler, P/S idler, ported exhaust mani's, ported lower intake, flowmaster exhaust, EGR delete, K&N filter, Darth Chip-- --13.8 @ 99 (before cams full street trim)-- --Check out the Fiero Kingdom!-- Beater: Flat black 90 CRX with a JDM D15 VTEC <--ballin'!
I could have that mount made, and making it an adjustable length was planned actually. It's just a pain in the ass to make threads with solidworks. And I dont know if those headers will ACTUALLY fit. It's hard to tell, but judging from other header designs that have been made, they should. By the way, I dont know if all my dimensions are 100% accurate on the dogbone. If i were to actually make it, which I'm seriously considering doing, I would need to take some accurate measurements in the engine bay.
And yes I know Aaron's headers are short because he's going forced induction. And there is really no way for me to varify in the virtual world that the headers i desgned are actually true equal length... but they should be damn close.
If I were to actually build a set of headers at this point it would be the shorty ones. And I dont have the money either way because I'm a poor college student, but if someone would like to build them I'll give you all the dimensions I have. BTW, all those bend radius's are mandrel radius's that you can actually find.
-Jeff
------------------ --180* t-stat, cams, 96-97 intake swap, FFP pulley, A/C Idler, P/S idler, ported exhaust mani's, ported lower intake, flowmaster exhaust, EGR delete, K&N filter, Darth Chip-- --13.8 @ 99 (before cams full street trim)-- --Check out the Fiero Kingdom!-- Beater: Flat black 90 CRX with a JDM D15 VTEC <--ballin'!
[This message has been edited by fieromadman (edited 11-08-2007).]
but if someone would like to build them I'll give you all the dimensions I have. BTW, all those bend radius's are mandrel radius's that you can actually find.
-Jeff
Send the longer set specs my way..I am building some custom headers for northstar and wouldnt mind doing some for the DOHC as well ..summit will be my christmas catalog
[This message has been edited by Erik (edited 11-08-2007).]
Those are going to be hard to give you specs on, but I'll see what I can do. And keep in mind right now i only have one side done for each and i'm not 100% certain that they will fit in the engine bay...
Jeff, Does your drawing for the idler pully/dogbone mount have the correct dimensions? If so do you mind sending me the SW file? Im gonna try to cut it out at the shop at mosy.
I have had on going idle/driveability issues with my car ever since I got the custom cams/96-97 intake manifolds put in it. Mainly the driveability is good, but the idle sucks ass. In fact, it seems that whenever it is below 2000 rpms and you aren't on the gas at all it runs like **** . 4th gear at 30 coasting you may as well forget about. Idling at stop lights, ditto, unless you are bliping the gas occasionally. And this idle is more than a hunting or rolling idle, it's a full on fledged I'm gonna stall and often do idle. I know that it is not the cams that are doing it because another forum member has the same cams in their car and it runs and idles fine. Although it has not been professionally tuned, neither was that guy's at first. All the sensors seem to be reading correctly, and since the engine has had the cams and intake manifolds on it has been gone over throughly, and the intake manifold gaskets were replaced (and torqued in the correct pattern to the correct specs), so I think that it is safe to assume that there are no gasket leaks causing the issue. There has also been a new chip burned by sinister during that time to give at least a base line tune on the cams. It made no difference. The cam timing has been gone over since this problem initially started. It's DEAD on now. The wiring harness has been gone over as well. The IAC was cleaned recently. The MAF was cleaned recently as well. It has no CEL. My crank sensor wires were cut by my pulley and that was fixed the last time the engine was out. I tried changing out the cam position sensor, that made no changes. I tested the resistance on the front 3 injectors to make sure that they weren't blown, they were good, and I know theres a 50% chance that one could be bad, but I dont think thats the problem. When I unplugged the MAF it acted like it wanted to die like it should. When it was on the scan tool the only thing that was out of whack was the fuel trim, it was all over the place. Everything else seemed fine. I tried playing with unhooking the TPS and the IAC. When I unplugged the IAC the only change was that the hunting idle stopped and it stayed at the RPM that I unplugged the IAC from. So that would make me think that something is causing the IAC to open and close. When I unplugged the TPS here are the results (video):
So possible problems that I can think of: Chip needing to be re-burned (sending in the paperwork within the week) Possibly needing CASE learn done Faulty wiring on the TPS sensor (I extended the wiring when I did the 96-97 intake swap and soldering or wiring could be bad) O2 sensor could be located in the wrong spot, or faulty. ????
Thanks for any and all help you guys can give! -Jeff
------------------ --180* t-stat, cams, 96-97 intake swap, FFP pulley, A/C Idler, P/S idler, ported exhaust mani's, ported lower intake, flowmaster exhaust, EGR delete, K&N filter, Darth Chip-- --13.8 @ 99 (before cams full street trim)-- --Check out the Fiero Kingdom!-- Beater: Flat black 90 CRX with a JDM D15 VTEC <--ballin'!
Jeff, Does your drawing for the idler pully/dogbone mount have the correct dimensions? If so do you mind sending me the SW file? Im gonna try to cut it out at the shop at mosy.
Not everything is correct. I really do want to build one of those though so I'll make them correct over thanksgiving and send the files to you (it's an assembly). I want to make the dogbone an adjustable length too, but that would be easy with some threaded ends.
We in California are having a hard time due to the Secondary Air Injection System we are forced to have on our cars. It’s not the manifold issue - If we can’t fine them we can make them - the pumps are readily available and the relay is a common one as is the check valves used. But the Electric Shutoff Valve is just to much $$$$$ Part number 12511251 for $385 and GM says only 10 left in the parts archive.
So here is the help I’m looking for.
This type of system has been used on several GM cars from the late 80’s to as resent as 2002. There have even been recalls on parts of the system and upgrades have been produced. Please help us non electrical experts and come up with a plug and play replacement.
My wish would be to have some cooler looking pump, say the one from the vet or the s-10, a compact electrical shut off switch (diverter) and a wiring diagram to go with it. I’ve been looking around and have found information on several other cars with this type of system but do not have the electrical expertise to glue it all together.
Any help would be appreciated.
Thanks
[This message has been edited by CC Rider (edited 11-21-2007).]
I dont think that the crank sensor is an issue. If I am wrong then that is something that I never knew about. The only additional sensors that the 94-95 system has is the MAF and the cam position sensor. Also, the MAP is not used with the 94-95 ECM.
We in California are having a hard time due to the Secondary Air Injection System we are forced to have on our cars. It’s not the manifold issue - If we can’t fine them we can make them - the pumps are readily available and the relay is a common one as is the check valves used. But the Electric Shutoff Valve is just to much $$$$$ Part number 12511251 for $385 and GM says only 10 left in the parts archive.
So here is the help I’m looking for.
This type of system has been used on several GM cars from the late 80’s to as resent as 2002. There have even been recalls on parts of the system and upgrades have been produced. Please help us non electrical experts and come up with a plug and play replacement.
My wish would be to have some cooler looking pump, say the one from the vet or the s-10, a compact electrical shut off switch (diverter) and a wiring diagram to go with it. I’ve been looking around and have found information on several other cars with this type of system but do not have the electrical expertise to glue it all together.
Any help would be appreciated.
Thanks
From what I understand of the system and from your post, the main obsticle is controlling the A.I.R. pump. It comes on for ~10 seconds when the car first starts and then is supposed to shut off. There are a number of off the shelf 12 volt timers that can do that for a lot less than $385.
That sounds great but I'm not taking any chances with the Smog Gods. I need it to as close to stock as possible. As I said above, I see that other cars have this same setup and my thinking is we should be able to piece together parts from other cars to get around this. I am not good at the wirings and I'm asking those that are to jump in and come up with a cost efficient alternative.
I found one on an S-10 and will be doing some bench testing this weekend. The diverter is not only vacuum actuated but the ECM applies the ground to turn the system on. The good thing is we have another LQ1 in the club and we can copy this car to get past this :^)
I want to make my application as clean as possible. The stock pump is an eyesore and large. I don't like all the plumbing that goes with the system and I want to hide as much as possible and make more presentable the parts I can not.
Again - I am not an expert on this stuff and I'm just muddling thru.
[This message has been edited by CC Rider (edited 11-28-2007).]
