^... What steps can I follow to determine this?

(My TBI is running RICH)

 

You can data log and see when you start getting 02 readouts. Is your TBi set-up the one in your sig? We may need a little more insite and what you have and how long the problems have persisted.

 

Data log as in WinALDL? It is sadly and annoyingly difficult to find electronic components in the part of the world I live. Canadian Radio Shack's don't even carry what I need.

I really don't know how long the problem has persisted. It has always smelled rich from the day I bought it (used). Now that the motor has been rebuilt, it still smells rich. O2 sensor has been replaced three times - which is why I am wondering if the ecm ever makes it into closed loop. Gas mileage is terrible too. Only 14 Imp MPG (11 US MPG) on highway, probably 10 in town.


My setup is the same as in my signature... It's actually an 89 blazer; but this is the by far the best TBI forum around. The parts picked for the rebuild are "supposedly" stock ecm friendly...

Is there "If this happens, then you are in closed loop" test which doesn't require data logging?


Thanks.

 

hook a volt meter up to the o2, if it is swinging it is in closed loop, if it is fairly consistant it is in open loop.

HTH,

BTW, without tuning with a large cam you will be rich at idle.

 

There in lies your problem. Nothing out there is really "chip" friendly to TBI cars. Since you have a 355 the settings in teh chip are no where near where they need to be. That is why you are so rich at idle. Chances are you are lean up top. You need to look into getting a new chip. Whether you do it yourself or have someone do it for you. That will cure your problem. These motors run like poo with the stock tune when parts are added to them.

I do mean WINDAL when I say data logging, you are right on about that.

 

Hmm.. I was afraid you were going to say that. Any opinions on the tbichips.com guy?

I contacted JET and they want $500US to burn a custom chip, which is out of the question for me.


I know I'm definitely not getting even close the true potential of my motor. I can't even light the tires up from a stand still on stock tires, open diff and 3.42s.

I think the giant snowball just turned into an avalanche...

 

JET chip is not the answer theyre way over priced and not exactly a custom chip. no chip is worth $500 in my opinion. The comp chips only cost a few bux to start with.

You may want to think about getting into it yourself! that is the only real way to realize the full potential of your setup. theres plenty of support and DIY Prom genius' here on TGO as well as tons of helpful threads to help the newbie out in this area. Plus if your over seas' I wouldnt think that waiting a 1-3 weeks for a chip to arrive is money well spent.

 

Z28GEN3 is right on. However, in the meantime if you just want to get your car to run normal contact Brian at www.tbiships.com and send him a few data logs and have him get you started. That should be enoughf or your car to run. Then you can take the time to learn the know how of doing it yourself. It is going to take a lot of burns but trsut me, when you get it right you will love the outcome.