Corsica misfiring after rain (nowadays problem with IAC valve)

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Money pit Beretta
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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

Post by Money pit Beretta »

Glad to hear that it is running well! Makes me think my girlfriends car could use a new computer. Been fighting with it for a long time now.


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GT_Indy
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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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Money pit Beretta wrote:Glad to hear that it is running well! Makes me think my girlfriends car could use a new computer. Been fighting with it for a long time now.
I worked with one of the guys who worked at the facility where they made our OBD1 computers. It was like a blast from the past for him when I met him.
He tried to show me where they worked on google maps but the facility doesnt exist anymore. lol

The 1227727 ECM is better than the 1227730 because it has components all rated for temperature and vibration.
Suposedly they dont go bad and fail like our ECM's do. The 1227727's also have O-ring seals on their boxes.


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Money pit Beretta
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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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Damn good info there! Going to start looking for a 1227727 as soon as I can.


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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Money pit Beretta wrote:Damn good info there! Going to start looking for a 1227727 as soon as I can.
It has its own pinnout and harness/plugs so be prepared to rewire that part of your harness if you wanted to use a 1227727 box. lol. I'm also not sure if it will fit in the space under our Beretta dashs.

There is an excel spreadsheet online somewhere listing the pins and matching them between the 1227727 and 1227730 boxes.


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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This box was fully working, but in the end it started giving the engine too much fuel on warm start ups. When i took the box out, actually from one connector there was one or two pins missing and misaligned... gonna try repairing that box when i got better freetime.

New boxes arent that much behind a rock... in example rockauto seems to offer remanufactures ecus at least for my -92/93 Corsica, dunno about Berettas.

About rough running... seems like i got another sensor hell to go thru. Car developed following symptom day ago:

1. Cold start up, no problems
2. Drive to grocery store, spend 30 mins there
3. Fire the car up while its been sitting on parking lot (around 30 degrees)
4. Let it idle for 30 seconds or more, suddenly idle becomes really rough and car starts jerking and stumbling.
5. Rev the engine couple of times, or put D on, everythings back to normal. This only happens if the car has been sitting longer time, with warm engine. If i just let it sit for couple of minutes, no problems at all.

Any ideas where to start at? Luckily, this kind of problem isnt that serious and can be lived with since the car is my daily driver atm. So far it has been running really great, also this symptom I just told about happens just in the conditions i wrote about (Maybe this sympton has been there for longer time, who knows...)


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

Post by Money pit Beretta »

WhiteGTZ wrote:
Money pit Beretta wrote:Damn good info there! Going to start looking for a 1227727 as soon as I can.
It has its own pinnout and harness/plugs so be prepared to rewire that part of your harness if you wanted to use a 1227727 box. lol. I'm also not sure if it will fit in the space under our Beretta dashs.

There is an excel spreadsheet online somewhere listing the pins and matching them between the 1227727 and 1227730 boxes.

Checked the year....I have a 95 so it's a no go. Not sure why I jumped the gun on this.


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Money pit Beretta
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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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Bapsu hope you find out what the problem is soon. My cars seems to do the same. Cold starts are great and it runs fine all the way to work. Starting at work is the same. If I go to the store it will then sputter start, running fine after that. Until this week, now on the way home it cuts out when the throttle is held at the same place for a long time.
Going to change the coils and then the fuel filter. Already put some Heet(to remove water) in the gas tank. That didn't do much. Starting to think there is a pressure leak in the fuel system. Could be the gas cap or a leak in the vent line(the one that is next to the filler neck). Had the fuel pump replace a few years ago. Makes me think somehow that the fuel pump seal is bad or leaking.

You have done so much to your car it's hard to pin point what it could be. I'll tell you what fixes mine(if I can fix it).


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

Post by GT_Indy »

Money pit Beretta wrote:
WhiteGTZ wrote:
Money pit Beretta wrote:Damn good info there! Going to start looking for a 1227727 as soon as I can.
It has its own pinnout and harness/plugs so be prepared to rewire that part of your harness if you wanted to use a 1227727 box. lol. I'm also not sure if it will fit in the space under our Beretta dashs.

There is an excel spreadsheet online somewhere listing the pins and matching them between the 1227727 and 1227730 boxes.

Checked the year....I have a 95 so it's a no go. Not sure why I jumped the gun on this.
I was thinking this could still work, then I remembered it would run the engine fine, but the trans is the 4T60e. You'd need a 5 speed or 4T60 non-e. lol.
I'm not sure if Code59 can operate a 4t60e, I don't know if the box has extra solenoid outputs for that either. Probably easier to OBD2 swap, I think the pin ends pull out of the plugs and can insert into the OBD2 plugs. Not sure. But in my opinion its easier to cut and solder. lol


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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Almost dream of OBD2 so I can get a check engine light. Have yet to get one even if it dies. Got some testing to do.....hope to find something.


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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Money pit Beretta wrote:Almost dream of OBD2 so I can get a check engine light. Have yet to get one even if it dies. Got some testing to do.....hope to find something.
OBD2 doesn't always know the issues either, of course. In fact (not really), I worked on a Ford that came up with the code P0000. Which of course merely identified it as a Ford! :D


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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Rettax3 wrote:
Money pit Beretta wrote:Almost dream of OBD2 so I can get a check engine light. Have yet to get one even if it dies. Got some testing to do.....hope to find something.
OBD2 doesn't always know the issues either, of course. In fact (not really), I worked on a Ford that came up with the code P0000. Which of course merely identified it as a Ford! :D
Our OBD2 Beretta's are not that bright either, I kept getting an idle code and an O2 code on my 96 3100 car, eventually I found one of the EVAP solenoids under the coil packs was bad, replaced it, then got an EVAP system code, replaced the other solenoid and it was fine again. lol


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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Money pit Beretta wrote:Bapsu hope you find out what the problem is soon. My cars seems to do the same. Cold starts are great and it runs fine all the way to work. Starting at work is the same. If I go to the store it will then sputter start, running fine after that. Until this week, now on the way home it cuts out when the throttle is held at the same place for a long time.
Going to change the coils and then the fuel filter. Already put some Heet(to remove water) in the gas tank. That didn't do much. Starting to think there is a pressure leak in the fuel system. Could be the gas cap or a leak in the vent line(the one that is next to the filler neck). Had the fuel pump replace a few years ago. Makes me think somehow that the fuel pump seal is bad or leaking.

You have done so much to your car it's hard to pin point what it could be. I'll tell you what fixes mine(if I can fix it).
Yah... I'll focus on the problem before autumn... been driving around now and havent faced this problem anymore in 2 weeks but there havent been much situations the car has been sitting for under hour and i go fire it up... i mostly drive to work and then some longer trips around.

I am thinking i got sensor problem since when my problem appears the car indeed runs really strong for first 30 seconds, then the sputter starts while ecu tries to set the idle to wanted range... maybe this Delphi ecu is having too much tolerance on fuel trims etc. and its not handling engine 100% like the original ac delcos ecu did (before it crapped out). I got another Corsica under work I stole this Delphi ecu from. Have to order original one later on this summer when i need another one for this project Corsica. Time will tell...

Atm the car has been my daily driver for almost 2 months, driven around 2k for now... so far i have just filled up gas tank and been really happy chevy owner. :P


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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Bapsu I dream of having two weeks without a problem. Do you have a nonGM crank sensor in your car? Really thinking that is my problem. Getting to the point where it is hard to drive. Funny thing is the sputter starts are not so bad. Those GM coils did something. Well this weekend will be the crank sensor and the ICM. Then on to the ECM if that doesn't work.
Rettax3: P0000...thanks, needed a good laugh!
GT_Indy: How did you figure that one out? I know it's related...in a round about sort of way. But man that was kind of out there!


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

Post by Bapsu »

Money pit Beretta wrote:Bapsu I dream of having two weeks without a problem. Do you have a nonGM crank sensor in your car? Really thinking that is my problem. Getting to the point where it is hard to drive. Funny thing is the sputter starts are not so bad. Those GM coils did something. Well this weekend will be the crank sensor and the ICM. Then on to the ECM if that doesn't work.
Rettax3: P0000...thanks, needed a good laugh!
GT_Indy: How did you figure that one out? I know it's related...in a round about sort of way. But man that was kind of out there!
I think i got original gm crank sensor on mine, at least i never did anything to that except measured the resistance last summer when i had misfire issue.

You mean hard start with sputter start? You have to crank? If the engine feels like running with less cylinders than 6 after start that propably means its getting too much fuel... maybe ecu for you also eh.

That project car is actually funny, coz before i started sorting out the water leak problem, i was moving the car to suitable place and it didnt start anymore. :D No crank on rev meter so i guess the sensor is gone. Should I rely on delco sensor in this case? What i have to take off for the sensor? Never changed that sensor on Corsica/Beretta.

I dont know that other problem, that when you are holding gas at same position for longer time. But I got slight feeeling in my ass that also my car is having very very slight stuttering sometimes when rising gas pedal up while slowing down from why speeds... it is really slight and often when i realize something is maybe stuttering, its already stopped lol.

I gotta work on that aldl cable indeed to see some datalogs mm.


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Re: Corsica misfiring after rain (nowadays problem with IAC valve)

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It is a normal start, but when it does fire off it is like it has lost a cylinder or two.
Just bought a GM sensor and put it in. That day it ran fine, then sat for a day and on Monday it would not start. Put the old one(BWD) back in and it still would not start. What's the problem? All I can say is that the wires were bare at the plug for the crank sensor. The strands were loose too. No sign of something chewing on them(still have not ruled that out). Got to go to the junkyard to find the wires on a 3400. They go from the ICM straight to the crank sensor.
What do you have to take off to get to the crank sensor? Nothing. Can say that it is easy to see between the engine and the transmission. To get your hand in there is not easy at all. You must go over the transmission a work your way around. It will cut your hands up pretty good. Hands: need the right one to get the bolt off with a 1/4in ratchet and a deep well 10mm. The left one works well for taking the bolt out or putting it back in.
A very long flat blade screw driver is great for getting the "plug"(or connector) off. That can be done between the engine and the transmission. At least you can see what you are doing on that. Was able to see the ratchet and get it on the bolt(it was tough though).
As a side note: the bolt is very long on the 2.8/3.1L, the 3100 has a much shorter bolt.


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