aaaugh 350 TBI fuel problems!!

[jeffluecke]

[ QUOTE ]
You can't tune with just the software. You have to get into doing your own chip burning.

Again I really appreciate everyone's patience with me as I try to get a grasp on TBI!!

I guess I'm not really that interested in tuning my TBI as I am with troublshooting what is wrong with it. I'm tired of throwing money at it and that really is not my standard approach, however when you don't really know what you are doing with fuel injection and you can buy a $10 or $20 dollar switch that you can convince yourself will fix the problems you are having, unfortunately that is an attractive alternative to taking the truck somewhere to have them put it on a scanner. I don't mind building the cable to interface with ECM with my laptop, however I don't have a clear understanding of whether or not any of these free downloads will clearly tell me what sensors are malfunctioning. The check engine or service engine light is not on after the engine is running. Keep it coming, thanks!!!!

 

[dyeager535]

Well, one sensor you can look at without any knowlege of the system and tell if its working or not, is the temp sensor. Either it's in a range that makes sense when the engine is hot or cold, or it's not.

TPS is another that is very easy to interpret and watch, to make sure it is working correctly.

You can watch the mV of the O2 sensor, which at least tells you if it's in a range that should be providing proper feedback. Even though the 160baud stuff is too slow to catch EVERYTHING, it's enough to see that the O2 is going rich/lean, and not just on one side or the other.

Vehicle speed, park/neutral, engine RPM, and AC requests are also there, and are easily interpreted. Not typically super useful for tuning, but sometimes there are problems with what the ECM is seeing for those inputs.

MAP is another thing you can look at, it's quite easy to read.

Many of the things you will look at can be interpreted by folks here, and if not, thirdgen.org, since there is a TBI forum over there.

Nothing out there, including the ECM throwing codes, is going to tell you what the problem is. The interpretation of the data it spits out is up to you.