Ok I recently purchased an iroc about 6 months and I am trying to get it to run correctly. i start the car and i have to give it gas to get it to run then once i let off it either stalls or idles really low and misses like crazy. I was told to check injectors ohms, they tested in order from 1 to 8 13.6 , 15.9, 13.4,13.6, 13.9, 14.1, 14.0, 13.6. I was told that they are weak then but does that mean i change them or not? , also some times when i start my car it idles high like then computer is in cold start then brings it back to a good idle rpm but still misses.. i think it should have a SES light on because its missing so bad but, there is no light so i tryed to start the car and unplug the tps to throw a code the light went off, and then i shut the car off and plugged it back it, but when i started the car again there was no SES light on. I was told that could be a bad ECM.. Also i think i read that the CTS on the front of the intake goes bad and causes a bad idle and also tells the fan when to turn on, and my fan doesnt turn on... but i no it works because we put power directly to the fan and it ran.. Ok. i think that was all my problems.. And it has a new tps and iac put on by the old owner.. soo can anyone help .. my dads a mechanic and can figure out anything but says if i want to be a mechanic i have to be resourcefull and figure it out myself so.. im hoping someone can help thanks

 

Does it run ok when you rev it up?

 

Ummm it clears up some but still misses alot

 

Ok. Do this, I got a 86 too. Remove the intake snorkel tube and remove the IAC valve. With your hand, hold back the spring and turn the needle in until it no longer goes into the motor casing. Now make sure that the hole where the IAC screws in is clean. If you see black in there, spray carb cleaner. Then screw back in the IAC (make sure that the gasket is installed to because if its not you'll have a vacuum leak. Now put everthing back together. When you fire up the camaro, the computer will close the IAC by itself. That's how to adjust the IAC valve. Now I highly suggest you follow this link. It shows you how to adjust your TPI system. Yes it's a Pontiac but it is still the same system.

1. http://74.125.155.132/search?q=cache...&ct=clnk&gl=us

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

After you do all of this tuning, and you still have bad idle issues, then spray carb cleaner on every section that involves a vacuum source such as throttlebody, vac. line connections, intake runner ports, and so on. If that doesn't work, then disconnect the MAF sensor and remove it from the Camaro. then get some sand paper or a Dremal tool and clean off the 5 prongs inside the wiring harness connector. then re-install and connect the MAF sensor. Next disconnect the battery for 5 minutes. then reconnect and turn on the IROC. Let it idle for about 5 minutes then take it out for a test drive. Park it. put in a prong such as a paper clip or a staple into the ADLD port under the driverside dashboard into A & B terminals. switch the ignition to "ON" but do not crank. The SES light will flash 1-2, 3 times, then pause. Now get ready to write down some codes. now post up the trouble code that pops up. then We can further assist you. Here is a website that will help you identify the trouble codes..... http://www.gnttype.org/maint/malf.html . Let us know what you get.

 

Thanks a bunch! I will try this all this asap is there anything u can tell me about my injectors tho? Are they weak and should be changed or ar they ok yet
thanks again

 

It all depends bro. Follow this link that I started on the 21st ( https://www.thirdgen.org/forums/tpi/...ml#post4417064 )

Look at the fuel injector that is in post #1. If your injector looks similar, and is probably rusted a bit, then youve got the original 19 injectors. I would changed them because they are 24 years old. Just read the thread and you'll get some info on where to buy 19 LBS Bosch III injectors for $160 (brand new set of 8). As for the resistance of the injectors, Im not familiar with the specs. Sorry. Hopefully someone else will read your thread and give you some answers.

 

Sound like the cold start injector in the back of the intake may not be working.

 

Even if the cold start injector doesnt work, the other eight do fire each side as a batch (batch fire as in the left side fire at the same time and the right side fire at the same time but they alternate from side to side. I was told this and you can verify by checking out a wiring diagram.

 

Ok I'll look into that also . It's gonna take a little bit before I get all my information back to you but hopefully I can get it fixed
thanks

 

K. Ill be around posting on the boards.

 

Your Ohm test is not horrible, once you start getting to around 9-10 or below you are better off getting rid of the injectors. Due to the fact that your are 24 years old there is still a good chance that they may be dirty, rusted, etc. At some point you probably would be better off replacing them, and yes i am in total agreement....bosch lll's are the way to go.

www.southbayfuelinjectors.com

 

Ok so today me and my dad decided to check out the charcoal canister, first we checked the pcv valve, once we were sure it was working correctly, we started the car and pulled the vaccum line off the canister on the solenoid, and the car actually ran better. Then we plugged the line with a finger or plugged it back in and it ran bad, and didnt want to idle anymore? so it ran better with a vaccum leak?? And the car ran very rich too,

 

Okay, with the vac line disconnected, what is the rpm's? Now put the vac line back (connected to vac cannister) and check the rpm's agian. If the rpm's are steady ( around 500-700) with the vac line disconnected,then the issue may lie in the idle stop screw. You might have to adjust that. What you have to do is turn the key to on but dont crank, leave it like this for about 20 seconds to give plenty of time for the IAC to close. Then disconnect the IAC so that it will not open when you crank the Camaro. Then turn on Camaro. now note the rpm's. Now adjust either turn the idle stop screw in or out depending if the rpms are high or low. If rpm's are high, then back off on the screw, if its low, then turn the screw so that it'll open up the throttleblades a bit. Make sure that the Throttle Position Sensor is within it's specifications of 0.465VDC to 0.615VDC (better if adjusted at 0.540VDC). Good luck and let usknow your results.

 

ok so are you thinking its too much of for where that idle screw is set at.. I am going tom. to work on it ill take my iac out and set the tps, but im still confused on the whole canister vaccum thing.. Why does it put suck a load on the engine. with it unhooked it runs beautiful, it has a small miss but its idles awsome, plug it back in and it runs horrible again..

 

My best guess is that if it's connected, your starving the engine from air. It's struggling so your pretty much choking it. Now when you disconnect it, the engine has enough air that the cylinder has enough oxygen that the combustion is now more effecient, reducing the rough idle. So I would definetely focus on that stop screw. Turn the screw with a torq clockwise so that it'll plunge and in doing so, the screw is pushing the throttle plates more open thus proving more air to the engine while at throttle. But make sure you set the Throttle Position Sensor at its minimun setting before making any adjustments to the Idle Stop Screw..

 

Ok so 2maro I am going over to adjust that idle set screw. Also before I go to work on it do you have any idea what the random miss may be.. I might just start with spring cleaning by changing plugs and wires. Then go from there any other things that could possibly go wrong that I could check

 

If ur experiencing a miss, make sure that the timing is at 6 degrees with the EST wire disconnected. Reconnect EST and disconnect the battery for 5 minutes so that ECM can erase the troublecode that is created when the EST was disconnected. Now reconnect the battery and turn on the car. If the miss is still present, then I suggest u to mark where the rotor and distributor base is pointing. Next pull out the dizzy (distributor) Now you'll need to replace the pick up coil, capacitor, in cap coil, new plug wires and of course the spark plug wires.

 

ok so 2night i set the voltage on my TPS, then i put the computer in diagnostic mode, unhooked IAC, and adjusted minimum idle air screw, the reconnected the IAC, back and it idles at 600 to 650.. Havent taken it for a drive yet.. Now i forgot to mention in the begining that my fan doesnt turn on even when the temp says it about 230.. Its got power and ground at the relay, so it must be in the signal circut.. Also my temperature gauge did work at first and recently quit working. Tried to ground out wire and the gauge jumped once.. so we plugged it back it back in and it didnt work, so we tryed to ground it out again and it does nothing? also i have codes 33 and 34 so...... 34 is maf right? dont no what 33 is, and if it is a sensor along with the maf should i just replace them or anyother ideas thanks

 

For your code 33 and 34, It's going to be your MAF Sensor. Follow this link http://www.gnttype.org/maint/malf.html
I fixed my code 33 by taking out the whole MAF Sensor. But first disconnect the battery to clear any codes. Now look under the sensor, there are 5 pins. Get a small piece of sand paper or even better, use a Dremel Drill and clean off the pins carefully. Your goal is to clean off the dirty coroded pins so that there is a good clean connection. Now as for the wiring harness that connects into the MAF Sensor, get the smallest flat head screw driver (jewelers screwdriver set Look at picture) that has the spinning top, and insert into the wiring harness connector. Now spin it around so that it'll clean off the internal surface of the connection. Once both areas are clean, reconnect both the MAF Sensor and the battery and turn on the Camaro to test it out. Drive around to see if that took care of the issue.
As for the fan, temporarily re-wire to check if the fan is burt out. connect directly to the battery. If the fan works, then the issue may be as simple as a bad relay. If the relay is good, then check the wiring. Below is a picture of the wiring diagram.

 

ok will do but do you have any idea on the temp gauge not working, also when i put the engine in diagnostic, the fan turns on so, it works but not when i want it to.

 

Only works while in diagnostic mode. Sounds like there is a issue with the ECM. How hot does the motor get before the fan turns on, if it does. Do you have a friend that works in the Air conditioning business? If so, ask if he can shoot a Lazer Infrared Thermometer at the cylinder head to see how hot the block is while idling and after a moderate drive. The goal is that you want to see how hot the block is so that you can troubleshoot whether or not the temperature gage is working in your IROC. Let me know what happens.

 

Ya we put direct power to it and it works then too so somewhere between there it ain't working.. Also hate to change subjects but could you give me a direct link to these bosh lll injectors that you recomend.. I think one of my injectors is ticking now and would be fun anyway to do some before summer injector swap. Plus I think the ones are oem on the car now

 

I hope you find the problem that ur experiencing. Well here is the link to the Remanufactured Bosch III injectors ( http://www.southbayfuelinjectors.com...ufactured.html ). Remember, if you decide to stay with the 305 block, then choose 19 lbs injectors. But u drop in a 350 block, ur going to need a 350 PROM chip from a 87 IROC Z or above(aswell as 22 lbs injectors). the reason is because our 86 is programed to function with 19 lbs injectors. As for me, since I got a 350 block, with 19 lbs, Im going to replace them with Bosch III 22 lbs injectors. As for my PROM chip, It's a Hypertech Chip model 127062 for my 350 (http://www.summitracing.com/parts/HY...n/?prefilter=0).

 

HAve you figure out the problem yet? My 87' GTA acts similarly at start-up. Let us know

 

Fan issues, Follow this link to see how my fan is controlled by the ECM. I believe that the issue of the fan turning on while in diagnotic mode is because the ECM is bypassing it's normal state, now while in normal state, the circuits are not triggering the chips to "close the circuit. Follow the link and you'll see that there is more processes inside the ECM. Your ECM may be similiar, but Im not sure. THe link is from thirdgen.org home page, Tech section. http://92b4crs.tripod.com/86wiring/dia-pics/31-1.jpg