Opel GT Forum banner

1 - 15 of 15 Posts

·
Member
Joined
·
179 Posts
Discussion Starter · #1 ·
I have a 95 Camaro 3.4 motor up and running on an engine stand in my garage. I had(have) the whole car so I decided to reconnect all of the wiring in an attempt to reduce the number of problems. I even have the gas tank and all hardware hooked up. The only things not connected are the cooling system, anti lock brakes and the power steering pump. I have reconnected all of the airbag sensors, head/tail lights and even the lighted rear view mirror.

The engine ran just fine when in the car... 55,000 miles on the odo, 155-160 lbs of compression and 800 rpm. But now it will not idle below 3,500 rpm. I took off the IAC and then the thing started and ran at 6,000 rpm - on an engine stand that is pretty scary. I have tested the resistance on the IAC and read 136 ohms. I am jumping the fuel relay because I have a broken wire in that line. Is it possible that applying 12 volts to the fuel pump is causing it to push too much fuel pressure into the engine? Would an ungrounded circuit somewhere do that? Other than that I think vacuum leak but I do not see any unconnected vacuum lines.

I have a 16 pin ALDL but at the moment do not own a Scan I to read any of the error codes.

Does anyone have any ideas? Thanks
 

·
boomerang opeler
Joined
·
5,636 Posts
first thing it needs is water in it as the temp sensor to the ecu will be going ape
does it use an air flow meter and is it connected ?
the pump is supposed to get 12v so it cant pump to much gas unless you do not have the pressure relive system hooked to return fuel to the tank
does it run a cat and if so is the lambda sensor wired up
just a few places to start
 

·
Member
Joined
·
1,709 Posts
If you take the iac off , you have major t/b air bypass & no control of
rpms. same as holding throttle open :eek: you must have at major vacuum leak somewhere. keep looking ( brake booster ? etc. ) you need to reinstall
the iac & run it down to idle postion with a iac tool or manually
HTH
 

·
Member
Joined
·
179 Posts
Discussion Starter · #4 ·
It has an IAC (Idle Air Temperature) sensor inbetween the air cleaner box and the throttle body - and yes it is hooked up. No air meter that I know of.

Fuel feed, return and vapor line are hooked up.

Cat is still hooked up to the exhaust manifolds... tail pipe ends about a foot out of the cat.

Would the temp sensor really have that big of an impact if I am only letting the engine run for a few seconds before shutting it off?
 

·
Member
Joined
·
1,709 Posts
the 95 has an mass air flow meter that has to be installed , iat sensor will
only cause a very rich condition , does need this connected.the iac is for
idle air control , the iat is the intake air temp.
 

·
Member
Joined
·
179 Posts
Discussion Starter · #6 · (Edited)
guyopel said:
If you take the iac off , you have major t/b air bypass & no control of rpms. same as holding throttle open :eek:
Yea found that out the hard way... shut it off within seconds of that mistake...

guyopel said:
you need to reinstall the iac & run it down to idle postion with a iac tool or manually
I have reinstalled the IAC... what do you mean "run it down to idle position"? I did make sure the valve pintle was screwed all the way into the actuator before reinstalling.

As for the brake booster line I have it blocked off.
 

·
Member
Joined
·
1,709 Posts
you went the wrong way down is high or max open :eek: you can get a tool to run the pittle out to close the passage or pull it out & try to reinstall with out binding ( trial & error method ) HTh I work at a chevy dealer & know this sys. :D
 

·
Member
Joined
·
179 Posts
Discussion Starter · #8 · (Edited)
guyopel said:
the 95 has an mass air flow meter that has to be installed , iat sensor will only cause a very rich condition , does need this connected.the iac is for idle air control , the iat is the intake air temp.
I believe only the 5.7 has a MAF... I looked in the Haynes manual and it refers to the MAF on the 5.7 only. Also I looked on my 3.4 and it does not have a MAF inbetween the airbox and the throttle body... ran fine that way when the engine was in the car.

guyopel said:
you went the wrong way down is high or max open :eek: you can get a tool to run the pittle out to close the passage or pull it out & try to reinstall with out binding ( trial & error method ) HTh I work at a chevy dealer & know this sys. :D
You are right. I installed the pintle into the actuator but made sure it was pulled as far out as it could be before installing again. Correct - right?
 

·
Member
Joined
·
179 Posts
Discussion Starter · #9 ·
Well I swapped the IAC today and still idling at 3,200 - 3,500.

Does anyone think the lack of a cooling system is causing any of this? I will try to get something rigged up soon but I am not convinced this is the problem.

Next I am going to disassemble the throttle linkage... doesn't seem like it is binding but will look anyway.
 

·
Member
Joined
·
179 Posts
Discussion Starter · #10 · (Edited)
15 minutes later and the problem is fixed... a nice 900 rpm hum... the key is in my last post.

The throttle linkage - or more correctly the cruise control linkage. When I took the engine out of the car I disconnected the cruise control. At the end of the cruise control cable there is a slide adjuster, and when I reinstalled the cable I tightened this adjuster too much... effectively holding the throttle part way open - thus the 3,200 rpm.

Wow... I can truely say "It's alive".

Next up - grafting the Camaro k frame to the tube frame under the car.

I am still looking for a good deal on a Scan I Tool. If anyone knows of a good deal or one that I can borrow (shameless plea), please let me know.

Life is good.
 

·
Banned
Joined
·
3,842 Posts
In that year range they did OBD 1 and 2 on Chevys tell me what the plug looks like. OBD 1 is square. Yes I have both.
 

·
Registered
Joined
·
6,344 Posts
Dave, just out of curiosity, what scanner do you have? Reason, I'm asking, is the Auto X-Ray scanner I have, and presumably others for the OBDII scanners won't read the 95 Camaro/Firebird/Corvettes without jumpering the plugs. I had that problem with Willit? and called the scanner folks and they have a jumper schematic on their website. This is the info they gave me: On the 5 pin (actually 10 pin possibilities) OBDI scanner connector, connect a jumper to pins A and M. On the car 16 pin OBDII connector the jumper from "A" goes to pin 5 and the jumper from pin "M" goes to pin 9. Another wiring mod I'll have to do, once I figure out which connector I'm gonna put in the car. But that's down the road a piece yet. Also, for the 95 year model they had the OBDII connector on some cars, which really screwed things up, and you can't use the OBDII scanner connector which is the reason to use the OBDI scanner connector and run the jumper wires. Also use the model year 94 and "S" model designator. I had a similar problem with Margaret's 95 T-bird, it had the OBDII connector but I had to scan it with a 94 model year to get it to work. The OBDII system was mandatory for 96, but the MFGs jumped the gun and put the II system plug in the 95 cars, but not the wiring to the pins or upgraded the computers to retrieve data. Lotsa fun.
 

·
Member
Joined
·
179 Posts
Discussion Starter · #13 ·
It is a 16 pin - 2 tall x 8 wide - rectangle... not the 12 pin. I dont know if it is truely a Scan II or if it is a later Scan I that used the 16 pin connector.

You borrow my glass - I borrow your Scan Tool?
 

·
Banned
Joined
·
3,842 Posts
if it's square it's OBD1. OBD2 is more triangle.
 

·
Registered
Joined
·
6,344 Posts
Oh Boy, it's not fun getting old. I just went out and checked my scanner. it has OBDI, OBDII and CAN capabilities. Looks like he has the OBDII connector from what he described, the 10 pin connector, OBDI will have to be used with the jumpers as I stated before and the 94 model year and model designator "S" plugged in to the scanner. Sorry for the confusion, the gray matter is slowing down in some areas. :(
 
1 - 15 of 15 Posts
Top