First off.. excuse this post of it already exist.. I tried to post to the 3rd gen specific about a half hour ago from my phone but I don't think it worked.. So..
I know its almost impossible to trouble shoot a car over the internet but I'm tired of spending money on my obviously below par guessing abilities.
A few months ago I drove my car "gt35r Streep port with pfc" to a friends house with no problem. After a few hours I went to start the car to let it warm up and I noticed the exhaust note sounded off.. no big deal as I have had this happen couple times due to a bad spark plug. I left the car and came back the next day to change the plugs. After changing them, nthe car sounded fine so I let it idle for a while and tried to give it some gas to see what happens. Now this is hard to explain but I will try my best. If I press the gas, it will rev and start to break up around 4500. If I repeatedly tap the gas it wil go all the way threw the rpms. If I try to hold the rpms anywhere in the rpm range it cuts out. At this point I was lost. I towed the car to my firends mechanics shop and changed the wires. No change. I replaced the coils and the igniter and still no change. I took apart the uim and checked the injectors and everything looked fine. I have good fuel pressure and I'm lost. I was thinking next to replace the map sensor and maybe the tps. When I removed the map sensor I smelled it and it kind of had the burnt electronics smell to it. But idk. I thought maybe the fuel pump or filter but since the pressure is good I kind of put those options in the back of my mind. I'm almost sure it has to be somthing electrical since it came out of no where with no warning. Any ideas what could be going on? I'm almost to the point were I just want to part the car out and and start something new. But I have had the car for almost 6 years and love it to death so that will be difficult to do..

 

do you have the powerfc commander? see if map readings match your boost gauge

 

replace your map sensor, and if you want to replace your secondary injectors to see if it helps i got some extra 1600's laying around that are brand new.

 

if neither of those options work though, honestly i'd try to get your hands on a new wiring harness, or have somebody completely redo your engine harness.

 

Yes I have the commander. When I compare the map reading to the boost gauge what exactly is the going to tell me?
I'm gonna change out the map tomorrow. I just have to find the same one I have Brian. Apparently all GM 3 bar map sensors are not the same. And there are plenty of them out there. But the part number should make it a little easier.
If that doesn't work. I want to test the tps too. I know that they don't usually go bad. But I might as well rule it out.
Then, if none of that works, I will probably stop by and pick up those 1600s and see if that makes a difference. But I doubt they will since to my understanding, the secondaries shouldn't really be doing anything in the low rpm range.. unless they are stuck open or somthing. o_O but I will let you know. If I have to **** with the wiring harness again I'm gonna go crazy!!

 

i understand yo, but you gotta remember this is the same old brittle wiring harnesss from 1993. matter of fact i'm probably going to get sean to redo my entire engine harness when i finally decide what i'm going to do with my car, lol

 

True.. me and Sean already replaced the entire body harness.. if it comes down to it ill take it back to him for the engine harness.. you ever finish up you headlights??

 

need to see Datalogit logs to troubleshoot.

 

Yea. I thought about the datalogit too.. but since this isn't the first time one would have come in handy. I'm just gonna go buy my own

 

if map sensor is bad, the boost gauge will not match it, they should read the same values or at least close. or at a minimum, make sure the commander readings changing and not stuck at one value. ive had a 3 bar map break on me, and it would only read 26psi boost

 

Thanks ill check it out tomorrow or Wednesday.. what sub category on the commander can I find the map read out on. I haven't messed around with it to much. But I don't remember seeing anything for the map on there. One more question. What kind of problems were you having when your 3 bar broke??

 

Corey,

Can you get the car over to my place? If so, I'll give you a hand looking at it. I MIGHT also have an FD harness over here that you can have. If I remember right, it's missing a few connectors, but those could be scavenged from your current harness if you need it.

 

Hey Reese,

I can try. I have have been moving the car around a lot since it started acting up smh. I am supposed to be finding a way to get it out to Gaston right now to work on it at Sean's place. I doubt that its a harness problem though. I will try to test the tps and map tomorrow after I leave from school.. do you know if our tps's are 5v units?? About to do some research on that now

 

Yes, the voltage to the TPS should be 5v+. To me, this does sound like the TPS 'could' be contributing to this.

How old is the fuel? Did you actually check the injectors to see how they are flowing? (i.e. did you pull them from the rail to see if they were actually spraying as opposed to just spitting fuel out?).

It's very odd that the car drove to your friend's house but developed this issue from sitting for a relatively short time...

 

Yea the injectors were doing what they were supposed too lol. (I had a big mess to clean up).
I thought about the fuel too. I had jus put gas in it that same day. So I was thinking maybe it was some bad gas. But I put a little octane booser in it and it didn't change anything. I went threw hell yesterday trying to find this same map sensor im using, so I just ordered a new on off the internet. Another thing is, a friend let me hold his 3 bar to try it out. It wasn't exactly the same as mine but I figured wth, its worth a try. When I swapped them out I had the same problem but 10x worse.

 

also need help on this... thanks for the heads up guys