Ok... I do not know where to start but here it goes..

I finished a 3800 series 2 SC swap, but the engine lately has been running very funny..

It misfires like crazy now, before it was just idling high, but now (without codes) the car runs like crap..

I checked all the coil pack resistance, I checked the ICM continuity, all the PCM wires are correct, it has all new plugs and wires and the injectors are all firing.

I took off the rear valve cover and everything seems to be in order.

If anyone has any suggestions to this obviously vague problem please let me know..

Its coming to a point of working on it for 3 years and putting about 10k into it, I just want to sell it for 1 or 2k and be done with it. I think it is quite obvious I have no idea what I am doing anymore..

Matthew

[This message has been edited by Matthew_Fiero (edited 08-08-2008).]

I know your frustration... My northstar swap seems to be one new problem after another. Im getting sick of messing around with it and just want to drive the car.
The best thing I can suggest is take a break from the car. I know when I am frustrated, things seem to get worse. If you feel like you are getting angry or something, just walk away and do something completely different.

Phil

Sounds like you could be trying to spark through a very small gauge wire possibly. Get the scan tool going to see if its a specific cylinder giving you issues, and go over you ground systems.

Hang on Mathew.
It's just a motor it isn't smarter than you.
Just take a breather, it is something obvious but you are too close to the forest to see the trees.
There are plenty of 3800sc swaps out there that are running fine.
Is your ICM grounded well?
Maybe the whole ICM is bad?
Was it running well when you first started it?
My opinion is if you have a 3800sc swap you are going to have to invest in a scanner that datalogs so you can get help when things go wrong.
Just hang in there, doubling your horsepower and torque will be worth it when you work out the bugs.

Trace your cam & crank sensor wires that snake their way between the pullys, pull them out (a b*itch I know) and make sure the wires are ok and have not been rubbing exposed on the crank (grounds out causing misfires) then put them back and make sure they are connected to the sensors, I spent days figuring out this simple error, FieroFlyer pointed me down this particular path.

I have a CAN OBD2 Code Reader, model 1003


It is giving me no codes, but all I know how to do on it is pull codes.

I have 4 grounds from engine to chassis and one large ground for the battery up front to chassis.

There is no point on taking a breather since I only work on the car now 2 times or so a week, in total in the past 3 weeks Ive worked on it 3 hours max.

If someone close by can come over and help me...I would be in their debt...

How long has the engine been running and did the engine ever run correctly or has this condition existed from the beginning?- I have a theory.

Matt, check fuel pressure?

I spent all day yesterday chasing a problem with one of our local fiero owners with a 3800 swap.




Anyways he had the car brought to me with some issues he's been having since the 25th show. He likes to shampoo the engine before every show and then he get intermittent problems while he's driving. He gets all sorts of codes the car runs very bad, it back fires it stalls and at times it does not even want to start. Well from the pass when this would happen we had issues with the wiring getting wet for the O2 sensor, then he had codes for the cam/crank, and so on. Well yesterday I went ahead and started the car, it ran some what ok but a loud hissing sound from the air intake. Then the car stalled, I scanned the car and had 8 codes, i wrote them all down and cleared the PCM. I ran the car aging and watched the readings. I found one of the codes to be MAF and seen no reading from it, I visually looked at the MAF and found the connector to be loose, plugged it back and wow it suns much better. Well after 8 min. of the car running it dies. Check codes, there are none, check to see if the SES is on and it's not. I keep starting the car it runs for a bit and then shuts off.
I look at the codes i pulled earlier and start from that. I started from the top and it's cam sig. error, check the sensor check the connector, check the wiring as far as i can, i perform the diagnostic test procedure and every thing checks out ok. At this point i put another cam sensor, try starting the can now it will not. I move to the next item, the crank sensor 18x. same thing check connector, harness, perform test and still come up all being ok. Next i replace the sensor try starting the car and no go..... aaaarrrrr..... Every time i it wont start no SES light?? so at this point i'm thinking PCM? oh by the way I did this swap maybe 13 or 14 years ago and used OBD I computer. I swapped out PCM for another one and still no start. hell at this point i went out for lunch when i got back the car started and ran maybe for a good 10 min. And then again the car quit running. I called the owner and had him ask me what he did to diagnose the problem, he had put in new plugs, a new O2 cleaned the ICM connector and greased it, and just made sure there was no other connectors that had any corrosion. At this point i still wasn't sure what it could be, so I then now was checking for fuel pressure. but the car did start for me and then while it was running it quit again, but the pressure was fine......I went back and looked at the codes from before and saw brake switch something, but this car is now manual so it's a code that does not light up the SES but it was not that, then he had an anti-theaft frequency error, but again three years ago we had it eliminated and for some reason it keeps showing this code. reading the manual it said that the car will start but not send an SES light, Then it one of the last ones was ICM interrupt problem? So now i check all the wiring to and from, check grounds, check power and so on, at this point i put a park tester on fire up the car and its fine.....hhhuummm.. and she quits within a min. I fire her right back up and she runs, then quits. Well at this point it's close to the end of the day and I'm frustrated. I had some one giver her a crank and i'm looking and notices no SPARK! I had him try it again and again and still no start NO SPARK..... I grab a used modual from a 3800 swap I'm doing into a 2nd gen Cavalier and installed it, car fired right up again. Now we wait to see it die....... 20 min. goes by and it's still running, I get brave enough to take her out and drive around the building. I must have done 40 laps and got dizzy so now i took it on the road, well to say it's okay.
What kept getting me was when the car was running and then it died i got no codes and no SES light, but i turn ignition off and re start the SES light came on until the car ran then it would go off.. So Matt don't give up..

When it's idling does it miss? or with some RPM?

Joe

[This message has been edited by Team Race-Tech (edited 08-08-2008).]

I am going to be coming back from Guelph on Sunday night from picking up a 3800SC engine and tranny I could stop by with my scanning equipment and see if I can figure out what is going on. It might be a little later in the evening depending on how things go picking up the engine but if that is ok with you I can drop by. Dan

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2003 3800SC series II powered
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A code reader scan tool is usless. You will need a scanner that will read simple obd2 data, and I suggest you get a scanner that reads both simple and enhanced obd2 data. If you have a laptop, I would get a autotap scanner with enhanced GM data.

Dan, my shift at Princess ends at 5:30pm on Sunday, I would be more than happy to have you stop by..

WEll guys.. Out I go, I'm going to booster cable from the battery to the motor to see if it is a ground problem.

This motor was running fine before I had to recharge the battery yesterday morning..

Since I have no software for my scanner tool, it is useless except for pulling codes, and I have about 10 dollars to my name.

There is no ignition modal on these cars so that rules that out..

Since There is nothing left to check (fuel pressure should be fine, new rails and new fuel pump) Nor do I know how to check fuel pressure.

I will keep everyone updated today.

Matthew

[This message has been edited by Matthew_Fiero (edited 08-08-2008).]

Uh, your coil packs are mounted on the ignition module, so yes, these motors have ignition modules. Take it in to your local auto parts store and have them check it. They'll want the coil packs taken off in order to test the ICM.

Can someone please give me a VIN # of a 1998 GTP so I can activate this software I got for my scanner please?

quote Originally posted by Matthew_Fiero: Can someone please give me a VIN # of a 1998 GTP so I can activate this software I got for my scanner please?

Title: 1998 GTX/GTP RAM AIR DAYTONA PACE CAR #033 SPECTACULAR! Mileage: 21,850 miles Location: Balsam Lake, WI Vehicle Information VIN: 1g2wp1218wf276955

If you need to change the vin, let me know, I think I have a program that will let you with most scanning hardware.

Fuel pressure is honestly the most common issue I see with 3800 swaps, as the regulators get clogged up after putting in a lower sitting fuel pump. The regulators are very sensitive.

I think its putting too much fuel

The engine is back to its normal running mode.. with a lumpy cam sound to it on low idle, then when the motor tries to correct itself, it stays at a steady, smooth 2k idle.

VIN: 1G2WP5210WF242628 non pacecar

Not sure if this is right..

DTC for which Freeze Frame was Stored P0000
Fuel System 1 Status Not Supported
Fuel System 2 Status Not Supported
Calculated LOAD Value 0.00 %
Engine Coolant Temp -40.00 °F
Short Term Fuel Trim - Bank 1 -100.00 %
Long Term Fuel Trim - Bank 1 -100.00 %
Intake Manifold Absolute Pressure 0.00 inHg
Engine RPM 0.00 rpm
Vehicle Speed Sensor 0.00 mph
Air Flow Rate Mass Air Flow Sensor 0.00 lb/min
Absolute Throttle Position 0.00 %

you have no maf readin and it is pullin 100 percent fuel/ and the coolant temp sensor is reading - 40 so the pcm has no signal from it was this thing runnning when you took this? now that i look again no rpm reading so it prob not running.. but you still have -40 coolant temp sensor reading with is defualt for the pcm if the sensor goes bad, there is one prob check wiring and you can check resistance on the sensor itself
32* = 5100ohms
77*=2000 ohms
86*=1600ohms
95*=1360ohm

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[This message has been edited by black88fiero (edited 08-08-2008).]

I hooked up a boost/vac gauge to the port under the supercharger snout, even in some decent revs, I am constantly getting vacuum.

How is this possilbe if the rotors are pushing air down?????? its supposed to be PRESSURE not Vacuum! Hense why the MAP is connected to that port...

Maybe this is normal and only produces boost under load?

Ehh, I would play around with it, you should be able to scan TPS, ect, iat with the engine not running.

quote Originally posted by darkhorizon: Ehh, I would play around with it, you should be able to scan TPS, ect, iat with the engine not running.

Not with this code reader lol..

This is the one I have
http://www.canobd2.com/Prod...496896883B73E9811175

Strange how I am getting vacuum on the boost point though..That means it could be giving me fuel problems as well.

MAP is working.. Even though when I unplugged it, the motor ran the same, I got a code once it was unplugged.

quote Originally posted by Matthew_Fiero: I hooked up a boost/vac gauge to the port under the supercharger snout, even in some decent revs, I am constantly getting vacuum. How is this possilbe if the rotors are pushing air down?????? its supposed to be PRESSURE not Vacuum! Hense why the MAP is connected to that port... Maybe this is normal and only produces boost under load?

The car has to have load on it to build boost, you don't wanna have + pressure in neutral now do you lol

Do you have a scan tool that reads the data?My mechanic says there way better.You can read what scensors are dead and just about anything else.When all else fails,take it too the shop for repair.

I wouldn't be able to take it to a shop since it is not road worthy, and besides, Im going to tell them I have a different motor in it and they're gonna turn me away.

Not only that, I know of no mechanic I can trust that would look at my car

Thank you for the suggestion though.

No shop will turn you away for having an engine swap, even GM will hook up a TechII and drive around in it and record data with the swap, shops will just charge you diag fee's. That can you pulled with P0000 is a default frame that stores defaults you need to pull the freeze for a code it throws. If you can start it and make it throw a code on something unimportant then you will get a frame with that code try unplugging your O2 and let the car run for the 40 seconds it takes to throw the DTC the vehicle uses the MAF to make the fuel tables untill the exhaust is warm enough to read O2 so its fine to disconnect it if the car is completely cool.

quote Originally posted by chaosfinity: No shop will turn you away for having an engine swap, even GM will hook up a TechII and drive around in it and record data with the swap, shops will just charge you diag fee's. That can you pulled with P0000 is a default frame that stores defaults you need to pull the freeze for a code it throws. If you can start it and make it throw a code on something unimportant then you will get a frame with that code try unplugging your O2 and let the car run for the 40 seconds it takes to throw the DTC the vehicle uses the MAF to make the fuel tables untill the exhaust is warm enough to read O2 so its fine to disconnect it if the car is completely cool.

I like that idea..

Its lame you cant scan misfires, that tool is hardly a tool.... its basically just a portable autozone.

I got some progress done today.. it runs smoother now, but the high idle is still evident.

I had a feeling thats what the P0000 was btw

[This message has been edited by Matthew_Fiero (edited 08-09-2008).]

Car hasn't started for 3 days now.

Cranks, but doesn't even try to start

I have spark fuel and compression..

[This message has been edited by Matthew_Fiero (edited 08-10-2008).]

quote Originally posted by Matthew_Fiero: I have spark fuel and compression..

Yes but do you have enough...

#1. What is your fuel pressure gauge reading?
#2. After cranking for a bit and removing a plug is it wet?
#3. Did you beef up your fuses for the injector banks. Are those fuses good?
#4. Was any reflashing done to your PCM or is it stock.

I'm no expert but it sounds like your PCM is toast or there is a short in a fuse or injector wiring (power or ground). If you have fuel and spark and your cylinders aren't wet I would think your injectors are not opening at all.
I could totally be way off but at the beginning of the thread I thought you had ICM problems. Then I woke up thinking you had crank and cam sensor problems (once again ICM). Now I am leaning towards a bad PCM or wiring problems.

If I were in your predicament, I would check my fuses, I would check my fuel pressure, (you can have 5 psi and that's fuel but it's worthless), I would take my ICM in and have it checked. If it turns out good I would suspect a bad PCM and would search for another one. I would then contact Sinister Performance to have it flashed to a 99 GTP. I would then rewire my pins to match the new PCM. I would recheck all of my grounds. If that didn't work I would consider setting it all on fire and putting some marshmallows on a stick.
Hope you figure it out soon.

quote Originally posted by Bubbajuju: Yes but do you have enough... #1. What is your fuel pressure gauge reading? #2. After cranking for a bit and removing a plug is it wet? #3. Did you beef up your fuses for the injector banks. Are those fuses good? #4. Was any reflashing done to your PCM or is it stock. I'm no expert but it sounds like your PCM is toast or there is a short in a fuse or injector wiring (power or ground). If you have fuel and spark and your cylinders aren't wet I would think your injectors are not opening at all. I could totally be way off but at the beginning of the thread I thought you had ICM problems. Then I woke up thinking you had crank and cam sensor problems (once again ICM). Now I am leaning towards a bad PCM or wiring problems. If I were in your predicament, I would check my fuses, I would check my fuel pressure, (you can have 5 psi and that's fuel but it's worthless), I would take my ICM in and have it checked. If it turns out good I would suspect a bad PCM and would search for another one. I would then contact Sinister Performance to have it flashed to a 99 GTP. I would then rewire my pins to match the new PCM. I would recheck all of my grounds. If that didn't work I would consider setting it all on fire and putting some marshmallows on a stick. Hope you figure it out soon.

Thank you for the input

I do not have a way of checking fuel pressure
I have beefed upo fuses but if I did not, it would not matter, they either blow or don't
PCM was reprogrammed by loyde.
No reliable shops here to check ICM
If its the PCM this car is going to the garbage

I have no time for this anymore, I think I've lost interest

I have a fuel pressure guage but you'd have to find the proper fittings and I don't know where on the 3800SC engine you can thread something in like that. I used to have it on the schraeder (sp?) valve on the fuel rail on the 2.8.

Might be more of a pain in the ass than it is a help?


Did you put a new fuel pump in?

My appologies for not making it last night with the problems getting through Toronto on the way to Guelph and a trailer tire slowly going flat I had to stop at almost every gas station to pump it up on the way home. It was after 1 in the morning by the time I was near Whitby so I just kept going and finally got home around 3 AM.
If you can wait a few days or so I will try and get down your way to see if I can help.
Don't give up on the car yet it most likely is some thing small and simple giving you trouble. Dan

How does one increase fuel presure anyways?

I already have a breand new pump, lines, filter and rail and regulator