Is it possible to erace the chip in the ECU by using a scan tool?

A little back round:

My Fiero was having strange problems when accelerating so a fellow PFF user offered his help. "very cool"
We listened to the Injectors to see that they were working. After that we hooked up a scan tool and took it for a drive. We wrote down the readings and compaired them to the readings we got of his Fiero " not all F@$#ed up like mine" Their was no real indicators of a problem pointing in any direction. I have had non stop EGR issues and the last thing we did was swap EGR Solenoids, and disconect the Batt. "to reset the ECU Codes" just to see if it would help but when I restarted the car It was Screwed. It sounded like I had blown a hole in the exaust somwhere or was running on 1 cylender. Every thing is wrong now.

So, Is it possible that when I disconected the batt and the scan tool was still pluged in it wiped the chip or fried the ECU.
If not what do I do now it is / was my only transportation. I have been told, to fix a exaust leak on the back side of the engine
I should drop the engine from the car. He is probably right but I want to be sure before I even consider a project of that magnitude.

Any thoughts?

Welcome to another AZ Fiero member.

If you short the two pins in the ALDL (ground and diagnostic in the picture below) and turn the key to Run, does the "Check Engine" light blink? If not, then you might have a bad ECM. If it does blink (one blink - pause - two blinks) then the ECM is okay. I don't think you can damage the chip ( PROM )without damaging the ECM, so the chip should be okay.

[This message has been edited by Steve Normington (edited 06-15-2005).]

yes, I can still check diagnostic codes I get the same old 32 but now I get a 33 also.
So if not the ECM then any other ideas?

What year is your Fiero? I assume it is the V-6 as you said you were listening to the injectors. If not, let me know. I have factory service manuals for 85 and 88. If you like, I can send you pictures of the diagnostic pages for code 32 and 33 for your engine.

Code 32 is for the EGR system. If this is commanding the EGR solenoid to be open at idle, that would account for the rough idle.

Code 33 means that the MAP sensor sees too high manifold pressure. This could be a leak in the vacuum lines.

Thanks for the replies Steve.
Yes, I am sorry; I should have mentioned I have an 86 GT w/ automatic. In addition, those pages would be great any info is appreciated. Rough idle is understating it a little. The thing sounds like only four cylinders are firing and very miss timed at that. Add the worlds larges exhaust leak and maybe some vacuum leaks to trip the MAP and you have a sound that has woke me in cold sweats the last few nights.

I am not discounting your advice but I do wonder could an EGR be this bad. I have always had a code 32 and have done many things to try to fix it. I.e. New EGR Valve, Vacuum lines and connectors, checked the tube to the upper plenum and replaced the solenoid from a one I bought off eBay. ” I’m not as yet sure that it works because this was the part I had just swapped with a good one when my new problem reared its ugly face.” I put the old solenoid back on, same thing. I should say the car did, barely drive home the night this started but with no power at all. 0-40mph in 45-60 seconds and 40 top speed. I do not know if this means anything or not to any of you but I get the feeling that I went from minor issues to major over haul.

I know the problems I am having is because I didn’t do things the right way before, i.e. diagnosing the problem not just trying to fix what I could and hope it would help. Again, my problem is I do not have money or time to throw at this thing. I will work on it every second I am not at work. I wish I could afford more but every penny I spend needs to be toward fixing the problem not just replacing every thing I can think of.

Due to the recent turn of events, I have new questions for you. Example

1. What diagnostic tools do I need to buy? Scanner
2. What are the cheaper alternatives? Scanner Software hooked to a laptop
3. What parts should I replace immediately? Distributor and Coil
4. Where can I get a service manual? “Helms”

I know I am asking for a lot of info but this forum is the only place I know of to learn this stuff.
Thx for the help,

Christian G.

quote Originally posted by cgoetzman@cox.net: Thanks for the replies Steve. Yes, I am sorry; I should have mentioned I have an 86 GT w/ automatic. In addition, those pages would be great any info is appreciated. Rough idle is understating it a little. The thing sounds like only four cylinders are firing and very miss timed at that. Add the worlds larges exhaust leak and maybe some vacuum leaks to trip the MAP and you have a sound that has woke me in cold sweats the last few nights.

I'll take pictures and send them to you when I get home tonight. I assume cgoetzman@cox.net is your email address?

quote I am not discounting your advice but I do wonder could an EGR be this bad. I have always had a code 32 and have done many things to try to fix it. I.e. New EGR Valve, Vacuum lines and connectors, checked the tube to the upper plenum and replaced the solenoid from a one I bought off eBay. ” I’m not as yet sure that it works because this was the part I had just swapped with a good one when my new problem reared its ugly face.” I put the old solenoid back on, same thing. I should say the car did, barely drive home the night this started but with no power at all. 0-40mph in 45-60 seconds and 40 top speed. I do not know if this means anything or not to any of you but I get the feeling that I went from minor issues to major over haul.

This is a long story, but it is worth it. I had problems getting my Fiero to pass due to high NOX. One of the things that cause high NOX is an EGR that won't work at all. One of the tests is you manually push up the EGR plunger to open it at idle. If you do this and everything is working, the engine will stumble. If you leave the EGR open, it will kill the engine. So I was thinking that a stuck open EGR or something similar would cause a rough idle. But replacing the stuff you've replaced would fix the stuck EGR. When you checked the tube from the EGR to the intake, did you check for cracks? Those tubes crack pretty easily and that would give you a big intake leak. That would cause the engine to run badly and give you a too high MAP reading.

quote I know the problems I am having is because I didn’t do things the right way before, i.e. diagnosing the problem not just trying to fix what I could and hope it would help. Again, my problem is I do not have money or time to throw at this thing. I will work on it every second I am not at work. I wish I could afford more but every penny I spend needs to be toward fixing the problem not just replacing every thing I can think of. Due to the recent turn of events, I have new questions for you. Example 1. What diagnostic tools do I need to buy? Scanner 2. What are the cheaper alternatives? Scanner Software hooked to a laptop 3. What parts should I replace immediately? Distributor and Coil 4. Where can I get a service manual? “Helms” I know I am asking for a lot of info but this forum is the only place I know of to learn this stuff. Thx for the help, Christian G.

No problem on the asking for help, that is what this Forum is here for.

1. A scanner is a really good help but they can be expensive. Forget the code readers, all they do is display the trouble code. You can do that with a paperclip. Auto XRay makes a nice line of scanners, but they can run into hundreds of dollars.
2. If you already have a laptop, then you can get a cable for $40 or so. You would also need software for it, but there are free programs out there for download. I don't know how good that one is, but you can download it and try.
3. Depending on how old they are, replacing the distributor and coil might help. Also replace the fuel filter (located on the bottom of the car, under the battery).
4. Check eBay for service manuals. You'll need one specific to your year car. If you see a manual that says it is 84-87 or 84-88, ignore it. That is the Haynes manual. The one you want is the factory service manual. url=http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7980659335&category=6762&sspagename=WDVW]This auction[/url] is what you'd need. There are other service manuals on eBay, you can check them out too.

I don't have time this weekend, but if you are still having problems next weekend, I can bring by my scanner, manuals (not same year, but close) and tools and we can see what we can find out about your Fiero.

Edit: I uploaded pictures of the Code 32 and Code 33 to my PictureTrail accountl. You can right-click on the links and download the images.

[This message has been edited by Steve Normington (edited 06-17-2005).]

Well back again, this time with a little more info on what it is not.

Over the weekend, Steve came over and showed me how to test things and what to look for. We ran some tests and isolated the problems with the EGR back to the Solenoid. Not to discount how good it feels to finally have a fix for the Code 32, but I have to focus on the problems with the idle.
I focus on the Idle because it is hardly drivable and Steve recommended we get it running first before we move on to performance issues. “Makes sense to me."
I replaced all vacuum lines again but with rubber tube, this time and I checked for leaks as I went around with my new vacuum pump and Injector cleaner. As per the Ogres instruction. Never found any. Therefore, I started throwing money at it. New battery, plugs, wires, cap, rotor. With no effect. One strange thing thou. The back three plugs were black with carbon.
I still get a code 33, "MAP too high" from my new scanner the MAP reads between 3.65v to 4.70 in the times I scanned it at idle. I know the range is 1v - 5v but my service manual has not arrived yet. So I don't really know what this means or what could cause it.
Finally, "for now" It has been pondered that maybe I have a dead CAT due to running to rich for an extended period of time. I found this in The Cave
() A quick way to test the catalyst is to measure backpressure at the O2 sensor port. According the June 2001 issue of Motor...
With the engine idling, the pressure will usually be below 1 psi on a good system. Backpressure reading over 1.5 psi is cause for concern. Next, bring the rpm to 2000 and check the pressure again. A good system will usually show less than 2 psi. If the pressure is over 3 psi, the catalyst is most likely going south.
Of course most people don't have the fancy commercial one of these lying around, but they can be made. You'll want to use some metal or high temperature flexible tubing to keep the gauge away from the worst heat. You also want a gauge made for low pressure, something with a 5-10psi top end. You can use an old O2 sensor or spark plug to fabricate the exhaust fitting.()
Question 1: What would create such a high reading on the MAP? Steve ran tests on the MAP and concluded it was functional.
Question 2: Why are my plugs fouled in the back, they are only maybe a year old? Is this part of my problem?
Question 2a: what is wrong with Bosch Platinum Plugs? Another post said these don't work in fieros and I don’t get why.
Question 3: Dose any one have one of these tools or know how I can buy or Build one?

Thanks for all the Help,
Christian G.

bump.......... hello

quote Originally posted by cgoetzman@cox.net: Well back again, this time with a little more info on what it is not. I still get a code 33, "MAP too high" from my new scanner the MAP reads between 3.65v to 4.70 in the times I scanned it at idle. I know the range is 1v - 5v but my service manual has not arrived yet. So I don't really know what this means or what could cause it. Finally, "for now" It has been pondered that maybe I have a dead CAT due to running to rich for an extended period of time. I found this in The Cave () A quick way to test the catalyst is to measure backpressure at the O2 sensor port. According the June 2001 issue of Motor... With the engine idling, the pressure will usually be below 1 psi on a good system. Backpressure reading over 1.5 psi is cause for concern. Next, bring the rpm to 2000 and check the pressure again. A good system will usually show less than 2 psi. If the pressure is over 3 psi, the catalyst is most likely going south. Of course most people don't have the fancy commercial one of these lying around, but they can be made. You'll want to use some metal or high temperature flexible tubing to keep the gauge away from the worst heat. You also want a gauge made for low pressure, something with a 5-10psi top end. You can use an old O2 sensor or spark plug to fabricate the exhaust fitting.() Question 1: What would create such a high reading on the MAP? Steve ran tests on the MAP and concluded it was functional. Question 2: Why are my plugs fouled in the back, they are only maybe a year old? Is this part of my problem? Question 2a: what is wrong with Bosch Platinum Plugs? Another post said these don't work in fieros and I don’t get why. Question 3: Dose any one have one of these tools or know how I can buy or Build one? Thanks for all the Help, Christian G.

The MAP reading of 3.6-4.7V at idle is way high, that is why it is running crappy and your plugs are fouling. Either the MAP has failed, or the vacumm line to it is leaking/disconnected. That high of a MAP indicates the ECM is dumping fuel in because it thinks you are at WOT (or close).
If you think the CAT is clogged, disconnect the exhaust from the crossover, while loud, it should run better. If it still runs crappy then it's not the CAT. CAT's usually clog because they were dropped, or the engine runs rich for an extended period of time, causing the CAT to overheat and melt the honeycomb material............Paul

[This message has been edited by Paul Prince (edited 06-28-2005).]

quote Originally posted by Paul Prince: The MAP reading of 3.6-4.7V at idle is way high, that is why it is running crappy and your plugs are fouling. Either the MAP has failed, or the vacumm line to it is leaking/disconnected. That high of a MAP indicates the ECM is dumping fuel in because it thinks you are at WOT (or close). If you think the CAT is clogged, disconnect the exhaust from the crossover, while loud, it should run better. If it still runs crappy then it's not the CAT. CAT's usually clog because they were dropped, or the engine runs rich for an extended period of time, causing the CAT to overheat and melt the honeycomb material............Paul

The MAP and MAP vacuum lines semm to be good. I hooked a vacuum gage to the intake manifold and it is reading 10 in Hg or so vacuum while the engine is trying to idle. I also applied vacuum to the MAP and the voltage reading from the scanner dropped.

Hey-
just wanted to see if any one has any new ideas on this
It has been over 110 here most of the summer so I have taken a few months off from my problems but the problem still exists. The most recent info I have to provide you is that I no longer have any error codes all have been fixed but cylinders 1, 3, & 5 are not firing at all. I know they are getting spark. Fuel? Compression?

I don't know, I need new Ideas, please

Check the fuses for TBI 1 and 2. One fuse can be blown and the car WILL run, crappy but it will run. Its a batch fire system and one side of the motor can and will scavenge fuel from the other to fire.

Just something else to think about....
88Ironduke

------------------
Pilots with out maintainers are just pedestrians with a cool jacket and sunglasses.
I.Y.A.M.Y.A.S.

quote Originally posted by cgoetzman@cox.net: Hey- just wanted to see if any one has any new ideas on this It has been over 110 here most of the summer so I have taken a few months off from my problems but the problem still exists. The most recent info I have to provide you is that I no longer have any error codes all have been fixed but cylinders 1, 3, & 5 are not firing at all. I know they are getting spark. Fuel? Compression? I don't know, I need new Ideas, please

That sounds exactly the same broblem than '91 Corvette we troubleshooted for a week. Scantool told that everything should be fine but engine stalled or idle was wery rought. We had broken injector. Measure all the injectors for resistance. One short circuited injector will kill half of the engine. Readings should be around 14 ohms. That means that one injector takes about 800 mA to open, 3 of them parallel takes 2.4 A.

I could not find info are 1, 3 and 5 in same group.

Take your own factory service manual:
http://spad.sytes.net/fiero/manuals/Pontiac_Fiero_1986_Service_Manual.pdf

I wanted to thank everyone who helped me with this 4 month venture.
I need to mention Steve Normington and cptsnoopy for donating your time and expertise. And last but not least the Award goes to "88 IRON DUKE!!!!!!!" you hit the nail on the head.

quote Originally posted by 88Ironduke: Check the fuses for TBI 1 and 2. One fuse can be blown and the car WILL run, crappy but it will run. Its a batch fire system and one side of the motor can and will scavenge fuel from the other to fire. Just something else to think about.... 88Ironduke

I have replaced every cheap part in this car, cut off my exhaust, torn down the intake assembly, throttle body, fuel rail, vacuum and ignition systems, some more than once. During July I spent three weekends in the garage one day my thermometer actually hit 117 in the shade of my garage. It all comes down to a F*@%ing 5 Amp Fuse. HAHAHAHAHAHa..Ha.......haaaaaaaaa.
I am just glad to have my baby back

The Black Bird is not yet ready for the show but at least she makes some noise again

Thanks again.