Nope, hes got a different setup. Ok, 88 TPI harness. Let me take a look inside my book. BRB in about 5-10 minutes.

 

ok , I suppose 2 rounded relay plugs and 1 square one like the one in my picture would let you know. If i could just find out what each of the plugs were for and some relay part numbers

 

alright thanks

 

Mass Air Flow relay =


Fuel Pump Relay =

Rdiator Fan Relay =

 

So if the square relay is for the fuel pump, and your fuel pump currently works without the relay, then there must be something wrong here. Perhaps there is a jerry rigged wire somewhere.

 

This may suck bro but your gonna have to open up the wire loom and trace the wires to their origins. But defenitely try to get the color of the wires for me so that I can further help you bro. I do not have any problems helping you out. Your questions are my missions. Well I gotta go bro. The wifey needs some special attention. Ill talk to you tomorrow buddy.

 

well thanks man it looks like i have some major work to do

 

ill let you know how i made out

 

So far what we know is the harness must be an 88. there are 2 round relay plugs and one square one. The plug i took a picture of is the fuel pump relay plug. Hopefully i can get to my garage today and get some work done,

 

One thing you should know. The fuel injection harness is completely seperate from the main electrical harness. The FI harness passes from the underdash to the engine compartment on the right of the car, just in front of the pass door. If you look just above the pass side kick panel, youll see where the harness passes through the body. There is no bulkhead connector in the FI harness. It is all one peice and has to be fed through the body opening to be removed/installed.

Ignition power is provided through the main engine harness on the left of the firewall, along with lighting and other accessory functions. All FI functions and any connection between the ECM and the engine is through the FI harness, including all FI related relay controls. Battery power to the relays youre looking at(MAF, FP, MAF burn off) is provided directly from the battery through a 30amp fuse that sits just beside the battery in a plastic housing.

Your diagnosis and figuring out what looks to be an awful mess need to focus on the FI harness and ECM wiring diagram. None of the ECM circuits pass through the bulkhead connector.

 

Well said ASE doc.

 

quick90rs, was there any relay connected to that square connector when you would turn on your TG?

 

there was no relay connected to that square plug

 

Now that is strange. If there was no relay connected, then the fuel pump would not turn on when the ignition is turned on. ,,,,,,.

ASE doc, hey buddy. How is it possible that the FP is turning on even if the FP relay aint connected? Im guessing that there is some kind of jerry rigging or non factory splicing somewhere in the wiring harness. quick90rs, when you installed the 88 wiring harness, did you notice excessive amounts of electrical tape or splicing in the wiring that is exposed to the engine compartment? If so, the wiring for the fuel pump may be wired to a "HOT" source. In other words the FP's power lead may be hooked up to a "ignition on" source. If this is the case, its dangerous because lets say you loose or burn up so much oil that the oil pump can not pump anymore oil. When there is no oil pressure in the system or the pressure drops below its rated pressure, the oil pressure switch "opens" the circuit which will cut off the power to the fuel pump relay, which will then shut off power to the FP, which will shut off the engine by means of shutting down fuel delivery. This is meant to protect the engine if there is no oil flowing through the engine.

 

But this is a worst case scenario. Still, having no relay and turning on has me .

 

ok im here with the latest update, on the MAF power relay plug there was a 12v source spliced into the tan and white wire. This finnally explains why the fuel pump never shut off when you turn the key in the on position. I fixed the wires to the relays and now the pump primes just as it supposed to. I have all my relays plugged in and the car starts great and the throttle response definitely improved, But in idle the RPM's are very low and the car has trouble staying running. So there still has to be some other problem. Does anyone think it could be the C207 connector needing to be pinned out?

 

HAHAHAHA. What a P.I.T.A. that was. I had a feeling that the wires were spliced into a ACC ON wire. Good for you bro. One major foul out of the way. Okay now. Im gonna send you a TPI tuning guide that will get your TPI up to par. Here you go......

1. http://www.highperformancepontiac.co...gta/index.html

2. http://mpikas.blogspot.com/2008/08/t...june-2000.html

 

The problem seems to be that your idle is way too low. When this is low, the IAC and the throttleblade stop screw are not adjusted correctly. You may just need to turn the stop screw clockwise just a bit to allow more air and fuel into the engine, but the issue may be that the TPS is not adjusted correctly either. It's a hit and miss situation IF you dont know what your doing. So go through the steps on the TPI tuning. It'll make your TPI perform at it's best if all components are working as they should be.

P.S.--- When adjusting the IAC valve, Clean off the black soot on the plungers cone shaped head. Make sure the "seat" inside the throttlebody is clean too where the cone opens and closes the port. Your gonna need some carb, or MAF sensor cleaner to spray inside the little IAC port below the throttlebody. You can use starting fluid too but I highly dont recommend this because it is far more dangerous. Now once the IAC is out, pull back the spring and turn the needle so that it'll screw in AS FAR BACK AS POSSIBLE. It'll stop plunging itself and you'll notice it when it will no longer go any further in. Now screw the IAC back into the bottom of the throttlebody. Once the IAC is back inside the throttlebody (make sure the gasket is still there), It'll automatically close the port when you turn on the vehicle. Good luck bro.

 

thank you, im going to have to try this tommorow. also i believe the TPS and IAC are from an 88 Camaro. Is that alright even though i have the 89 chip? are the sensors the same?

 

Yes. Your IAC and the TPS are good to go. The TPS is not realy a sensor, but more of a potentiometer that sends a voltage to the ECM depending on how far or less the tangs position is according to throttleblades/gas pedal.

 

And the IAC is just a motor that opens and closes a port via shaft and cone plunger. It's controlled depending on what the whole gang of sensors are reading and sending.

 

It does not look like I have solved this problem. I was working on it yesterday and i couldnt even get the car too start. I took another 165 ECM i had and put it in. The car started right up, and idled great, throttle response was better. I though i was done, i went to take it for a ride and I still felt like even though the throttle response was better the cars power wasnt all there. I pulled over and noticed one of the vacuum ports on back passenger side of the plenum were disconnected, when i capped the port the cars idle dropped, the car was shaking, and it wouldnt stay runnning. I dont know what to do now. I have not pinned out the C207, could that be the problem?, Could the MAF sensor be the problem? How do i diagnose the MAF. Any help would be great.

 

Bingo!!!!! This may be the issue that you are having. Since you capped off the 1 of 2 male ports, you changed the amount of air entering the intake. In other words you changed the "idle air" and your choking off the engine. Here is a diagram of the vacuum line configuration ( http://chevythunder.com/fuel%20injec...um%20lines.htm ). Trace your vacuum lines and make sure that they are all connected. When you verified that all is connected properly, then disconnect the battery for about 1 minutes with the headlight switch pulled out to drain any lingering current in the electrical system. Now reconnect and readjust the the TPS, and the idle stop screw to get the recommended idle RPM. You dont have to readjust the IAC, or the timing. That should get you going.

 

did you ever figure out which plug is which and did you ever solve your problem. im having the same problem with my tpi 305 after buying and rebuilding the engine. if the car was running in order for it to sling (before i purchased it) then the MAF clearly worked then. relays and fuses normally get burnt out or shorted when screwing with battery connections. so maybe when i was disconecting and reconecting the battery i shorted my relay out. atleast i hope thats all it is. but i am having the same exact symptoms.
im going to be cleaning my MAF tonight and checking the relays tomorrow.

thanks

 

Thank you. I will check my vacuum lines and make sure there all right then do this and let you know what happened, Hopefully i can do this tommorow

 

I also do not have a vapor canister or an EGR solenoid in my car if it makes a difference

 

Hmmm. I don't know if not having them will make a diifence. Vapor can just pulls the vapors from the tank and egr solenoid allows exaust into the combustion chamber to keep the upper cylinder from getting too hot. Having a upper cylinder too hot can result in damaging pinging (engine knock).

 

Keep in mind, high cylinder temps can also damage factory valves, piston, and rings. Even without pinging.

 

Well I believe I have the EGR solenoid from my 1990 Camaro TBI. Is it the same for what I need now? If not which one should i be getting for the system i have now? also some pics would really help

 

I believe the EGR solenoid from your RS should work fine. Is the harness connector the same?

 

So after gettting nowhere with my car I had a friend of mine who is a mechanic look at my car. Turns out there are cylinder misfires in cylinders 6,7,and 8. There is spark there but when i remove wire 6,7,or 8 from the distributor cap the car doesnt change the way it runs where as if i remove say wire 2 the car would change. This car ran beautifully with TBI so i know it is not a hardware problem it must be a wiring problem. Does anyone know of something wire related that could be causing this? I have not pinned out the C207 and pin B1 is broken on the ECM. PIN B1 is Battery 12V B1 Orange wire

 

HHHMMM. Perhaps;
1. Bad Ignition coil
2. Bad wires
3. bad spark plugs
4. bad rotor
5. bad ignition spark control module
6. bad dizzy cap

If you have the Large cap dizzy, I would replace everything inside such as the Ignition control module (4 pin or 7 pin) Pick-up coil, rotor, Ignition coil, and or the cap.

 

I thought about this but if I have spark at every cylinder how could the be causing the misfire

 

Theres either arcing somewhere in the plugs (check at night time to see if there is any blue sparks) or those injectors are bad. Didnt you just get some new injectors though? Or was it someone else?

 

no new injectors but newer plugs i am thinking this is something to do with the wiring harness possibly nut just dont know what. If it were the injectors it seems weird how they are cylinders 6.7.8

 

put a noid light on the harness plugs for 6,7, and 8, if the light doesn't flash you may have a couple broken wires. Also ohm test the injectors, if you haven't already, they should all be around 16 ohms.

also you really need to fix that B1 situation, that wire is part of the power supply for the ecm, this could be part of your problem.

 

Is the VSS signal hooked up to the ECM?

 

whats a noid light and where do i get one. also is there anyway to fix the pin without buying a new ecm. Also, "zepher" i have a VSS buffer box and the VSS is connected because the speedometer works

 

A noid light is a fuel injection test light, it plugs on to the f/i connector and flashes when the plug is grounded by the ecm. Any decent auto parts store should have it.
As far as repairing your ecm, I couldn't tell you without seeing it myself, but the 165 ecm was very common in the mid to late eighties. almost every gm pfi car used it, you should have no trouble finding another one.
your local pick and pull will probably have a few of them.

 

so there is a possibility have this pin broken could be my problem

 

Could be since it is a power source for the ECM. Also the fuel injectors are fired by batch. In other words, the left side all fire at the same time as well as the right side but in a alternating rythem. John 89 Formula is correct. I agree 100% with him. If you got spark at the spark plug, them there may be that issue with either the F.I., F.I. wire or even both. Keep us posted with your progress.

 

what do u mean by fuel injection wire? and i will keep everyone posted

 

The wire that the fuel injector connector is on. If you follow the wires back you'll find that the black wires with the stripes (pink or green) on each side are spliced into one that goes back to the ecm for ground. I think the pins are d15 and d16.
Same for the 12v side except it goes to the fuse box (inj1 inj2).
The 12v side can be checked with a test light.
the ground side you may have to visually inspect each wire from the plug to the splice to make sure there aren't any damaged wires, but I really doubt that this is the case
get your ecm squared away first and go from there.

Pin c16 also carries 12v to the ecm but where there are 2 different pins i would think that each one powers a different part of the ecm.
that could be why some stuff works and some stuff doesn't.

 

Actually, all 8 fire at the same time. There are 2 fuses, one for each side but only 1 injector driver.

 

I would have to disagree with your claim. No offense but I got a friend that was a GM mechanic. Also if you where to stand infront of the IROC with the hood open, you can hear the FI alternating ( if you have Bosch III's).

 

Any more news on this problem? I have a customer car with similar problems.