ItstillaV6

Thanks, that helps out a lot. I really didn't want to pull the plenum.

Just curious, what is the CTS stand for? I won't have any trouble finding the wires, but I want to know what I'm testing there.

Maverick H1L

iTrader: (8)

Sensor (and other) Definitions:

Blower: HVAC fan... In HVAC case near passenger's side hood hinge
CTG (the way I abbreviate it, anyways): Coolant Temp Gauge sender/light switch... Driver's side cylinder head, behind A/C compressor, by lifting eye
CTS: Coolant temp sensor... Sensor in intake manifold behind thermostat housing
Fan: Radiator fan(s)
HVAC: Heating/A/C system
IAC: Idle air control motor... 4-wire unit in throttle body
IAT: Intake/Inlet (depends on what store you go to) temp sensor... either in the Camaro dual snorkel intake or air filter can
KS: Knock sensor... Down by starter, acts as the coolant jacket plug for the passenger's side of the engine block
MAP: Manifold Absolute Pressure sensor... Mounted on bracket mounted to cowl near middle of car just above the corner of the HVAC blower case
OPS: Oil Pressure Sensor and/or Switch: Screwed into the oil filter adapter, 2.8s have a 1-wire for the gauge and a 2-wire for the switch. Later cars have a 3-wire doing both at the same time
P/U: Pickup coil... Inside distributor
VSS: Vehicle speed sensor... Transmission tail housing on driver's side near trans mount

2.8 cars (in case someone with a 2.8 is looking here for help):
CSI: Cold start (7th) injector... Down near dizzy base in the back of the intake manifold
CSS: Cold start injector switch... Near CTS, has a BLUE injector connector on the top
MAF: Mass Airflow Sensor... Either next in line from the air filter can or the dual intake, large black cylinder with a box attached to one side

ItstillaV6

I have a couple updates, on my troubleshooting, to share.

First, I pulled the IAC valve cover plate, off the top of the throttle body. ****Note**** DO NOT DO THIS, unless you plan on using silicone to make a gasket. I cleaned everything out, and added a bead of silicone to each side of the gasket. The gasket list price, from GM, is $28.59 and discontinued. Autozone, NAPA, Advance, and O'Rielly's can't get it either. I called 4 GM dealerships, gave them the 8 digit-GM part number, and every single dealership had the wrong gasket. This did, however, fix a vacuum leak.

Second, I tested the resistance, on the fuel injectors, well some of them. I did the test, after the car had been driven. So, my engine was at operating temperature, and my thermostat is a stock 212*open/195*close. The Pink/Blue(odd cylinder bank) turned 4.9-5.2 ohms, and the Pink/Green(even cylinder bank) turned almost the exact same reading of 5.0-5.2 ohms.

I then tested the #1 cylinder injector, and my reading turned back 13.4 ohms. My #6 cylinder injector turned back 13.4 ohms, too. I know that heat increases your electrical resistance, slightly. I don't think my injectors are bad, but I haven't eliminated the possibility of them being clogged or my pressure regulator being faulty.

This car did a LOT of sitting, prior to my purchase of it, 3 years ago. I purchased it, with only 100,826 miles, and have put over 70,000 miles on it, over those 3 years.

I plan to replace my O2 sensor, just to be safe, and will need to buy the proper fuel pressure tester, before I can test my fuel pressure.

My questions now pertain to these:

1. Are those resistance readings normal, for the engine being around 190-200*F?

2. How do I find Southbay, in the event I need a set of injectors? A lot of members here, have purchased their injectors, from Southbay, but I can't find a link or a web page, when Google searching them.

3. The fuel pressure regulator is "non-serviceable". Where are some good places to find a new/reman fuel rail assembly, if I need to replace my pressure regulator? (List price, from GM is over $750 and it is discontinued)

4. As far as the ECM is considered, as it may be a problem still, where is the best place to order an ECM? Autozone can test mine, and the replacement they carry is supposed to be ready to install, and comes complete with a OEM PROM installed.

5. Is it possible, the leak in my #5 cylinder from the exhaust manifold studs being broken, enough to cause my stalling issue? The reason I ask, a friend of mine has a "stud puller", that uses a ratchet and has teeth for grabbing a broken stud. You just turn the ratchet, and the teeth self adjust, dig into the stud, and it turns it loose. I want to try the tool, since my studs are broken flush, with the manifold itself. I'm neither a fan, nor in a position to have the head removed and drilled out, atm. This is my daily driver.

6. What is a good place, to purchase the fuel pressure tester, for fitting on our Schrader valve, on the fuel rail?


Thanks guys, again, for all the helpful information. The last 3 years, this site has been the only site I have preferred to use for troubleshooting. The process has been very slow, finances have been holding me back, but you guys have been patient and helpful, and I appreciate it greatly.

Maverick H1L

iTrader: (8)

A little late for you now, Itstilla, but those looking for the TB upper plate gasket should look here:

http://shop.advanceautoparts.com/web...14985|L3*15347

I couldn't get my TB plate to seal worth beans after the gasket was ruined (and yes, I used RTV), so I went and got this kit (used to be a GP Sorenson kit).

FPR diaphragm:

http://shop.advanceautoparts.com/web...14985|L3*15355

Knock down the pins in the middle of the FPR screws if you can't get your hands on a T10 security bit.

ItstillaV6

Thanks. I'm going to order the gasket set. the gasket doesn't show to be an exact fit, but it looks very close, to what I need. Otherwise, I may go get a used throttle body, from a boneyard.

As far as the FPR goes, I don't know if I need it yet, but how do I change that diaphragm? I have the tamper-proof torx bits, to get the screws out.


Also, I have another update. I was successful in repairing the exhaust manifold stud AND getting the gaskets installed. I recommend new donut gaskets, as GM used a machined gasket that doesn't seat in the manifolds(go ahead TRY to line them up during reassembly). I used the stud puller and the bolts came right out. Apparently, those bolts are cast iron, not steel. Therefore the can seize, but it is less likely they will seize.

*****NOTE***** O'Reilly's can special order the EGR gasket, that fits on the valve side of the tube, for a low $13.99 + tax. I used the EGR gasket from the Mazda 2.5L engine, from the old Ford Probe. It has the exact same shape, with a slightly smaller span between the bolts.(you have to thread the bolts through the gasket holes), but it works.

******NOTE****** The EGR tube, that comes off the manifold to the valve, has a machined finish. IDK if they make a gasket for that. I was advised to use red silicone. Not a fan of silicone, to begin with, let alone on a 900* exhaust manifold.......

I also got the pleasure of replacing the #3 cylinder expansion plug, with the engine still in the car.(I'll NEVER do THAT again!!!!!!) Lesson learned! next time, I'll pull the engine. I want to thank the guys, on here, that suggested using the neoprene rubber expansion plugs. $2.99 a plug, but they are a "one and done" scenario. Easy to install. Fixed it, and within 3 days, the #1 expansion plug started to leak(coincidently, it is partially blocked by my timing cover gasket)

So, got everything back together, fuel economy improved, stalling still present at idle and during deceleration. Unplugging the knock sensor still corrects the stalling and some of the misfire, but now that I don't have as many vacuum leaks, it REALLY DROPS MY MGP(recently tested this and avg about 20mpg on the highway @ 65mph)


Was given the suggestion, that i may have a burned valve, from the manifold leak going on so long. So I'm going to do a compression test soon, and find out what is going on there too.

Maverick H1L

iTrader: (8)

Replacing the FPR is probably going to be one of the easiest things you've done yet. Remove the screws in the cover (knock down the pins in the middle of the screws with a punch if you have to... I broke my security T10 so I had to do this), take the cover off, pull diaphragm out. Reinstall with new parts.

The compression test will yield lots of info. If the compression is low between 2 cylinders, it means the head gasket should be replaced (mine went twice between 3 and 5). If you can, also check the head and block if you need to do a head gasket. I should have done so with mine, but I replaced the heads instead (needed too much work already and you can't beat what I paid for the 3100 top end except to get it free).

Red RTV is only good to about 400*. Use copper, which is good to about 700*. Yes, I know, the exhaust is still too hot for the RTV, but I have yet to see any high-temp RTV that the guy who made an appearance at my school mentioned when I specifically asked...

ItstillaV6

The good news: I don't need to do compression test, to figure out what is causing my misfire.

The bad news: My exhaust has informed me of the problem, namely, by spitting out gobs of water at normal operating temp.

ItstillaV6

I recently decided to test my off-road capabilities, with my thirdgen. Drove through a very deep body of water, and by "deep" I mean about 8-9" deep. Needless to say I was unsuccessful after the all 6 of my cyclinders filled full of water and locked up my engine. Upon pulling all 6 spark plugs out, I noticed all 6 were about the same in wear and color. The plugs were fairly white, and I have been driving with the knock sensor disconnected to prevent detonation and high combustion temps.

My guess was the car is not getting enough fuel, since I know the timing is retarded from the knock sensor being disconnected. So I did a fuel pressure test. Here are my results:

At idle, with the engine at operating temperature: Steady 36 psi.
When I opened the throttle to rev up the engine, the pressure immediately jumped to 42 psi, and gradually decreased to 32 psi. *****Now I figure when the throttle opens, vacuum signal decreases and slowly increases as the engine revs up.
When I disconnected the vacuum assist, from my IAC valve line, to the FPR, the pressure increased to a steady 46 psi.

My Haynes manual lists the fuel pressure range should be between 34-47 psi for MPFI engines.

So, can anyone shed some light, as to where my lean condition is coming from? Would it be injectors, the fact that I have no smog pump, or the ECM? I think I have eliminated fuel pump and FPR, as they both seem to be functioning correctly.

Maverick H1L

iTrader: (8)

1. Fuel pressure, GM spec, is 37-47 PSI. All models except carb and toilet bowl. IDK where Haynes gets their info, but it apparently isn't GM service manuals...
2. Smog pump doesn't matter. I've never had one and never had any issues with running lean.
3. From the sounds of it, your plugs are fine and so is the AFR (I got 30 MPG with plugs looking like that). The issue may or may not be a loss of compression somewhere.

Since I can't remember at this point, have you already tested the CTS' resistance and compared it to the IAT when cold?

ItstillaV6

CTS was replaced, when I purchased the car, and cooling fan kicks on at correct temp. I haven't done the resistance test, yet
I can test em. Just give me the specs, and I'll get you the results. Also, I did pull the ECM, and I did not see and physical damage or burnt circuitry. I even pulled the blue cover offy PROM, to be 100% sure, there weren't any burnt circuits. I even tried sniffing, as a burnt circuit, has a very distinct scent. Nothing red flagging the ECM as defective.

Maverick H1L

iTrader: (8)

I forgot to add in my last post that the FPR is acting normally...

When the throttle is opened less than WOT (allowing full atmospheric air pressure into the engine), the first thing that happens to the engine vacuum is that it does drop for a moment, and then it INCREASES as the engine catches up. If you had a vacuum gauge, you would notice that the idle is around 16-18" and then drops quickly to around 5 or so when the throttle is opened before it goes up to around 25" or so. As the vacuum increases, the fuel pressure drops.

ItstillaV6

Thanks everyone, for all your help with this thread. My Camaro hit the end of its lifespan, today. Natural causes of a Cadillac pulling out in front of me, in an intersection. The front bumper is part of the dash, now. I wasn't injured and my seatbelt stopped me from hitting my airbag. She is totaled, though. I did save the custom parts and stripped her engine clean. Hopefully, I can get another 3rd Gen, and transfer them over.

Stewie

It pains me that your car was totaled. I've spent so much $$ and even more time on my "baby," I think I would be depressed for weeks if mine was totaled. On the other hand, I often see some good sales on the Third Gen Camaro & Firebird classifieds. However, let me suggest you get a Firebird next time -- just for the cup holders. Just kidding, but let us know the details when you get another 3rd Gen.

Shaggy2015

so tonight my camaro began to idle rough i looked at it for a bit and all vacuums were good tried unhooking egr valve nothing changed unhooked what i believe to be a sensor on the left side of the throttle body (there were 2 connections) when i unhooked the top one nothing changed unhooked the bottom one and my idle smoothed out but when i hit the gas and let out it stalled hook it back up and it starts idling rough anyway point it does anyone know what that part is called so i can order it it is on left of the throttle body where the intake comes in from the hose and is a sensor on bottom and has a female connection with 2 pins thanks for any help any ideas as it has been running rich knock sensor, maf, o2 are all new

willexoIX

Start a new thread.

92RS-HeritageEd

iTrader: (2)

Hey,
not to impose on your thread but I was wondering if anyone could tell me when idling how many RPM's should be registering in the Instrument Panel. Currently it registers anywhere from 10-20....my RS dies (Stalls out) at anything below 10. HELP would be appreciated.
Thank you!

34blazer