Switch B and C.

Okay, bringing my thread back alive. Havent worked on my fiero since the last post. I tried switching b and c and no different. I have the extreme cable from Moates now so I'm going to get some readings for Darth and I'm going to try a different coil pack. My local O'reillys dont have the equipment to test coil packs, but I already have a different coil pack. Dying to drive my fiero, I'm having withdrawals.

So what is it doing now?

It tries to start but immediately dies with a little backfire. It seems like it is trying to fire on the wrong cylinder. Since I did the 7730 swap and the roller rockers at the same time I'm curious if the rockers being overtightened would cause this.

So I have been working with Ryan a lot trying to get this started. Have resolved some issues but currently I'm trying to figure out which terminal is A and B on the crank sensor. Originally when I was told it didn't matter if they were switched, know there is some discussion on it. Neither the crank sensor or the connector is marked on mine. I want to be able I to make sure and match things up in case it really does matter. Thanks again as always.

Does the engine crank faster than it did before? Have you checked your compression on your cylinders to at least know you are in the ball park on the rocker adjustments?

The compression is what it was before I changed the rockers, 185 across all cylinders, and if I unhook the fuel injectors it cranks fine. It only gets hard to crank when it is trying to fire. I can here the compression going into the intake like it is trying to fire at the wrong time.

Does it crank like this? When a cylinder fires it 'stops' the cranking for an instant.



If so there is too much advance.

[This message has been edited by phonedawgz (edited 11-04-2011).]

Yeah kind of like that with a little backfire. I'm using the DIS and crank sensor so no way to adjust the timing. I'm hoping that maybe if the two crank sensor wires are switched that would cause it to act like that.Can't tell if they are switched though. Need to figure out what side of sensor is A and which is B.

The internal crank sensor or one that is added to the front of the crank?

On the crank pick up - the A and B are on the wire harness connector itself

Hold the connector's wire in your hand - so the connector is pointing away from you. Have the connector's clip on top. A is on the left (Yellow) and B is on the right (Purple)

The same applies for the ICM plug but the wires go to A - left - yellow and C right purple.
There is no wire in the middle B pin of the ICM plug, unless it is the shield wire.

[This message has been edited by phonedawgz (edited 11-04-2011).]

That is where y issue is. The connector I'm using isnt the actual crank sensor connector it is a recycled one from the distributer, and it has no A or B on it. So with clip on top that means mine is backwards, so I will switch it and see if it makes a difference. Thank You.

It appears I am having similar problems. My car ran after the 7730 swap, but has never run good consecutive days. I got a good deal on a trueleo intake so when I went to install it I replaced vacuum lines, followed your ideas wig removing cold start injector and sensor, and removing water lines running to TB and not using the lines on the trunk wall. I also replaced all o rings, caps and seals on the injectors, soaked them in seafoam a few days. Got the engine back together, and my car is acting just like yours. Keep us up to date. All though I didn't go dis with 773/ so my problem is not the crank sensor.

Well, it sures feels F...ing good to drive my fiero again. switched the wires on the crank sensor and it fired right up. Thank you everyone for the great help. Far from done however. It is not idling very well. It has a hunting idle up and down and sometimes dies, so guessing I have a vacuum leak somewhere. If I throttle it up it back fires a little so I'm going too check the plugs to see if there fouled and get some fresh gas. It has been eight months since I drove it last. The exhaust was a consiistent whitish color so I'm assuming water in the gas.

It does seem louder on the top end than what I remember, but when I use the stethoscope, it doesnt seem loud around the valve covers, hard to believe all that noise is the injectors.

My next step is to get it hooked pack up to the computer and get some readings.

Rained all day so didnt get it down to get gas in it. Hopefully the weather will give me a little break tomorrow. For no here are some more pics. We all love pics.




And my other project


Right hand drive, swapped it over myself.


Front mount intercooler still need to relocate the battery and run the piping for it.

Just a question then on the pick up wiring. So is the combination that works A-A and B-C?

Yeah, that is what I have. And I also have the sheild wire hooked up to B on the coil pack side. Drives me crazy all this time and it was that simple, granted I didn't work on it much over the summer.

Heres a video of the idle

Ok I put this video on youtube trying to get it to embed here cant figure it out. So here is a link to it.


http://youtu.be/Nq36RuMRn1Q

Okay here is a good link for a good video. Any ideas on why it is idling like this? All my vaccuum lines seem fine. I used rtv and gasket when installing truleo.

[This message has been edited by fierofinder (edited 11-06-2011).]

syntax - but make the last bracket square -

[youtube]http://www.youtube.com/watch?v=Nq36RuMRn1Q&feature=youtu.be[youtube}

What have you done with your tune? Anything or still what was on the chip?

Do yo have a scanner for the 7730?

[This message has been edited by phonedawgz (edited 11-06-2011).]

Havent done anything different to the tune, just what Ryan did for me. After I got it running good and get all the kinks out I was thinking of having him do a full tune. I'm just about to hook up to tuner pro know and see what it says.

Edit: Thank you phonedawgs for the video.

[This message has been edited by fierofinder (edited 11-06-2011).]

Great to know! Time to figure mine out since we have a similar setup. Unfortunately I don't have a crank sensor so that isn't my problem. Good looking cars.

https://www.fiero.nl/forum/Forum2/HTML/119668.html
In this thread Raydar talks about 17# camaro injectors being disc type and suggests getting the pintle type otherwise the disc type can cause a hunting idle. I have the 17# camaro injectors. Does anybody know anything about this.

Check your "Voltage at Fuel Pump" with TunerPro. Does it vary up and down with the idle? Mine did and I needed to adjust the "FUEL INJ OFFSET VS. FUEL PUMP VOLTAGE" to make the hunting go away. I'm running 30lb injectors with the 7730. Both code59 and $8F required tweaking to make the hunting stop.

It has something to do with how the Fiero is wired. Checked at the battery the voltage is solid but the ECM is wired such that it is sensing slight changes as the rpms vary. Maybe the combo of injector type and fuel pump voltage sensing are the issue? Some have also added better grounds to fix the problem. I believe this is related.

Voltage at fuel pump is steady no variance according to TunerPro. I looked into the injector thing and found out that I should be fine with disc type since I'm running the 7730. Few things I'm going to try but is most likely going to be some vacuum leak I'm overlooking. Always seem to be something simple when You spend a lot of time on it.

Give it a good rap with the handle of a screwdriver and see if that frees it up. Worst you can do is break it.

A closer longer look at it and they all seem to be firing. They sound different through the stethoscope though. Four of them sound like you can here the fuel and two sound dry. To explain it better all you can here is the ticking on two and the other four there is something else going on, a background noise.

With my ear down in there as the idle hunts everytime it revs back up i believe i can here a little whistle sound, cant pin point it yet.

Also it seems to have a lot of whitter smoke. Maybe because there is still some older gas in there, or because it goes rich as it hunts.

quote Originally posted by fierofinder: A closer longer look at it and they all seem to be firing. They sound different through the stethoscope though. Four of them sound like you can here the fuel and two sound dry. To explain it better all you can here is the ticking on two and the other four there is something else going on, a background noise. With my ear down in there as the idle hunts everytime it revs back up i believe i can here a little whistle sound, cant pin point it yet. Also it seems to have a lot of whitter smoke. Maybe because there is still some older gas in there, or because it goes rich as it hunts.

The injectors should all sound the same thru the stethoscope. If you have some injectors that sound very different from others, that could be an indicator that those injectors are dirty or partially clogged. It is common for injectors to become clogged when they sit for long periods of time disconnected from a fuel system, or even connected to a fuel system but have bad gas run thru them.

-ryan

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OVERKILL IS UNDERRATED

Custom GM OBD1 & OBD2 Tuning | Engine Conversions & more | www.gmtuners.com

Unplug the IAC while the engine is running faster to stop it from surging. Not a fix but to be used to try to diagnose the trouble.

I did that earlier. It does keep it from surging as much. I'm lost though. been out there for awhile working on it. Tried putting the old injectors back in from the 2.8. Didnt want to stay running with those unless I gave it some gas and it didnt seem to solve anything. Can't afford new injectors. bought these remanufactured camaro ones when I did the 3.4 swap. I put JB Weld over any little pin holes in the truleo welds and when I installed the truleo I used rtv so I cant see that leaking. Seems like it is going to come down to something electronic again.

I really think it's a rich/lean thing.

Does the surging happen when the engine is cold?

Does unplugging the O2 sensor change the surging?

What happens when you electrically unplug the MAP sensor?

Your MAP and fuel pressure regulator are connected to a good source of manifold vacuum? The vacuum lines are not leaking?

[This message has been edited by phonedawgz (edited 11-08-2011).]

Have a good vacuum source to both MAP and pressure regulator. The car dies if I unplug the MAP. Nothing changed with the 02 sensor disconnected. When its cold you can tell it is still there though it isnt as bad because it is revving higher when cold.

Today I finally took the time to hook the air compressor to the intake and spray some soapy water on there. I set the air pressure to about 5 psi and just blocked the throttle body with my hand. Right away I started finding leaks. I know pushing air through is a little different than sucking air through it. The suction can help create a seal where as the blowing can push air through easier. One place that was leaking alot was the short metal line coming from throttle body to lower intake. easy fix there. The other leaks were all in the Truleo intake. Found several leaks in the welds just on the one side didnt spray on the backside of it. Going to contact Francis and see what he will be willing to do for me. Worst case scenario is I'll JB weld it. Think I'll take this oppurtunity to pull the whole cradle and clean things up in there. It will be my winter project. I have lots of plans for it. I think I'll start an actual build thread.

Spring bump...ever figure out your idle problem?