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Discussion Starter #1
Ok guys, a quick project recap, this is driving me nuts!

I did Koni inserts and B+G springs in the front of the car, about 4 weeks ago. Car sat in the driveway, but I started it every week and let it idle and warm up.

Could not drive the car because it still needed new rear brakes, and I had the springs to put in the back as well.

4 days ago I pulled car into the garage. While it was in there I did some minor tune up things that needed to be done at the time:

Re-torqued the rear head and installed new spark plug wires (just the rear three, my brother put the front 3 in when I was doing the front suspension work, and didn't want to tear the plenum off to the the back ones)

I also put a new thermostat in at this time while I was doing the head and plug wires. I also put a new grommet on the idle air sensor so it would fit in the opening better, it had become somewhat loose and wasn't sealing.

Put all that back together and also did:

New rear calipers
New drilled and slotted rotors
New Pads
B+G rear springs

So after 4 days of straight work, I bleed the brakes and put the car back down on solid ground, and NO IDLE!

the car will start, for about 1-2 seconds, it will revv up (by itself) to about 3000 RPM, then just cut. It will do this every time, if on the way down I catch it and give it some gas, it sputters and revvs unwillingly, and dies still.

My only thought is it is the Idle Air Flow sensor, that before because it was loose it didn't matter if it was working or not, and now that it is in there tight, it could be malfunctioning....

Any advice here?

I am ready for this project to be done!
 

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How about the brake booster hose did it come off intake or crack? sounds like if you have all ectrical wiring hooked up correctly you have a big false air leak.
 

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Discussion Starter #3
Which is brake booster?

Two vacuum lines on the front of the plenum, one small going to the fuel line, the other bigger, is that brake booster?

Could that be causing?

Also, what is the single screw that sticks out of the top of the throttle body?
 

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Which is brake booster?

Two vacuum lines on the front of the plenum, one small going to the fuel line, the other bigger, is that brake booster?

Could that be causing?

Also, what is the single screw that sticks out of the top of the throttle body?
Black "plastic" booster hose goes on back of intake between Idle Actuator and throttle body accel cable bellcrank.

Small Front hoses for fuel pressure regulator vacumn and cruise control/fuel evaporator cannistor vac bottle inside left fender.

Don't adjust that screw it is preset for throttle body idle stop.
 

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Discussion Starter #5
Well, I think I messed up then, I turned the screw thinking it was something else, so how do I get back to normal now?

This is what I've gotten so far:

It will rough, (very rough) idle now at about 2000 RPM and eventually die with IAC wires disconnected from back.

I think I messed something up between the IAC and the throttle adjustment screw...

As for leaks, the hoses are intact all around, they should be fine because they are new as well as the big intake corrugated hose.
 

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You need IAC wires hooked up to get a correct idle. and if you turned that screw in you opened throttle body up and now min max switch is out of adjustment. You need to back out screw to where you think it was preset.

Then you need to see if min max switch will click on/off between 0<1 degree. If you haven't adjusted min max switch on front of throttle body back off screw you adjusted in until switch clicks 0<1 and you will probably have screw back in correct reset position.

Also inspect connectors to air flow meter and idle actuator to be sure wire terminals are locked into connectors so terminals will actually connect to pins in AFM and IAC.

Report your results.
 

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Discussion Starter #7
Connectors are in good shape and making contact.

Backed out screw for click between 0 and <1 degree. Plugged connector back into IAC- also checked shiny, hard black plastic booster line, everything looked intact.

With IAC plugged back in, experiencing same behavior as very first post:

starts and revvs to 3000 and immediately dies.
 

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All your hoses hooked up including one from oil seperator to rear valve cover and to intake corragated hose?

Booster hose hooked to valve in brake booster pancake hidden under firewall?

AFM flapper vane not stuck?

Intake plenum grounded to engine with grounding strap if rubber mounted and fuel injection ground wires bolted to intake?
 

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Discussion Starter #9
Brake booster hose should be fine, it was never touched and was functioning before I drove the car into the garage 4 days ago...

Maybe one of the grounds on the plenum (the 2 heavy gauge on the passenger side) is not contacting properly? I will make a new grounding strap from plenum to engine, however plenum is not mounted on rubber. I have no idea what I touched that screwed things up so much!

Would the IAC have anything at all to do with this?
 

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You said you retorqued rear head so you had to remove intake plenum. Lots of hoses including booster hose hooked intake system so just trying to give you a checklist.

It acts like you have a false air leak and throttle body switch out of adjustment.

Is throttle cable working correctly. Guess if you can adjust screw for preset idle stop it must be so retrace your steps and see if you can figure it out.

Inop IAC can make it not idle but false air and mis adjusted min/max switch can cause high idle.
 

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Fuel lines around pressure regulator near airbox inlet correctly connected?

Used to have cars that were not getting fuel due to a plug/kink somewhere downstream of the pump, so would start from residual pressurized seeped fuel but lean out instantly, causing the engine to momentarily rev, then die. I wonder that if the regulator is hooked up wrong, residual pressurized (from trying to start the car) fuel would seep into the injector lines enough to start the car, but once it does start, the mis-installed regulator might then shut off the fuel needed to run the engine. Just a thought.
 

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Discussion Starter #12
I think I have checked everything. I have checked:

The two bigger lines running to the IAC and the Oil vapor canister from the intake line.

The line from the Oil vapor canister to the valve cover

The Brake booster line from the back of the plenum

The Two front Vacuum lines, (replaced both because they were cracking)

Took off the intake just to make sure the throttle was not stuck open or something...

Looked at the AFM, took the cover off the bosch unit and the arms looked fine and the action was fine.

Am I missing something big here? Experiencing the EXACT same behavior, revvs to about 3000 then instantly dies.

Fuel lines look fine, they were never touched and the car ran perfectly 5 days ago!
 

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You broke something now what was/is it?

Did you disconnect 3-wire connector to min/max throttle body switch when you took off intake plenum?
 

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Discussion Starter #14
Is that the throttle position sensor on the front of the throttle body?

Yes that was disconnected when plenum was taken off, I'll spray some contact cleaner in there and see if that helps anything.

I do tend to think there is an air leak somewhere, but I have no idea where!


Time to start troubleshooting...
 

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Is that the throttle position sensor on the front of the throttle body?

Yes that was disconnected when plenum was taken off, I'll spray some contact cleaner in there and see if that helps anything.

I do tend to think there is an air leak somewhere, but I have no idea where!


Time to start troubleshooting...
Yes that is the switch that has to click on/off 0>1 degree. Be sure wires to it not broken and as I said it clicks correctly. It is adjustable by loosening those two mounting screws and rotating to set clicking.
 

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Discussion Starter #16
So the car will run in the 3000 RPM range, but no lower. This leads me to believe there is air getting in somewhere or faulty AFM because it needs so much fuel to get it to keep running?

Does this make sense?
 

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Discussion Starter #17
Ok, I am hearing 2 different clicks upon opening up the throttle. One click comes just upon moving the throttle (between 0 and <1 degree). The second click comes at about 1/3 or 1/2 throttle open...Are the separate clicks supposed to happen at once? The first is slightly louder than the second?

How could I have messed this up so badly? I didn't even touch the TPS!
 

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You're not missing something big here, more likely something small. Two cooks in the kitchen is not a good thing. Are the plug wires installed correctly as in, the correct wire going to the correct cylinder? Recheck your brother's work, what else did he do? Also, don't start messing with AFMs and stuff you didn't touch before, cause it didn't break while it was just sitting for 4 days. Take a deep breath and retrace all steps, but don't start making new ones just yet. I think we need to get the factory throttle butterfly stop screw setting instructions out. You have a Cardisc manual?
Charles
 

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Discussion Starter #19
Car runs smooth at 3000 RPM, I triple checked the spark plug wires, front and back.

I am positive it has to be something with that throttle screw, as its the only thing I messed with, but I dont know how else to adjust it. I have a cardisk kicking around here somewhere, I have to locate it, but would that single screw be causing this?
 

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I believe so.
 
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