GM TBI swap,running way way way rich..need help

[broncomitch]

many of you know I switched from MAF efi to GM TBI.

I got the harness all done and right off the bat it had problems, long cranking, had to hold it wide open to start, running very rich to the point its pinging and such..and wont rev past maybe 2000 RPM without back firing and knocking and such...

I replaced the coolant temp sensor and MAP sensor and O2 sensor and it fires right up now but still runs way way way rich..
so rich that within seconds of running the shop is filled with smoke and your eyes are burning...

I'm super frustrated and sick of working on this POS...

any ideas on what's causing it?

 

[broncomitch]

 

[flexyfool]

Scanner information would be helpful.

Is the fuel pump compatible with TBI? It should put out around 18 PSI. I'm thinking the Ford MAF is 40 PSI.

 

[broncomitch]

Don't have a scanner for this setup

 

[bryson]

The symptoms you describe sound timing related to me. Has the timing been double and triple checked? Distributor was installed at TDC #1 on compression stroke? Could the timing gears/chain be off a tooth?

 

[broncomitch]

I'm sure the timing is off a bit..

for some stupid reason the distributor will only come in and out if I crank the motor over...

so I need to bring #1 up to TDC mark where the rotor is pointing and adjust from there wile I crank the motor to seat the dissy.

I barrowed a carb so I'm going to put that on and get the timing set and cinda go from there....

I also can't put a timing light on it cus my water pump blocks the marks on the crank..

 

[broncomitch]

We'll I put a carb on and it fired right up...I did find one problem...I forgot to plug the old O2 sensor port on the left side..but apart from the carb flooding out it runs grate..


I missed the sound of the secondary's opening up on a carb


I also found this on my adapter plate...

Cinda Looks like the adapter is bent in the middle and was sucking in air passed the gasket...
Or is that just me?


The gasket is really really thin too..

 

[broncomitch]

Well, I took the carb off and put the TBI back on with a thicker gasket and it starts and runs a lot better...

still runs like crap and way rich but major progress with it...so much so I moved it from the abandoned side of the shop to the middle

slowly making progess with the pig.. Think there is still something wrong with the timing cus holding at half throttle it stumbles really bad and cinda starts to die. cinda wonder if the vacume advance isn't working..?

 

[skiboarder]

Give b2 bomber a shout. He has done several of these, and will be doing mine later this week.

 

[Cascadia]

Do you really not know how to spell the word kinda? Not trying to be rude.

 

[skippy]

An LS would fix the issue

 

[broncomitch]

D o you really not know how to spell the word kinda? Not trying to be rude.

I kinda do...
but mostly don't give a shit.

But I would kinda recommend that if you don't like how I spell cinda, don't read my post's and and just stick to pirate.

Kinda don't mean to be rude.. :thumbs:

Kinda.

But.......kinda.

 

[broncomitch]

Give b2 bomber a shout. He has done several of these, and will be doing mine later this week.

Will do!

An LS would fix the issue

At this point I wouldn't care if it's the motor out of a peddle car!
I just want to get it on the trail..

 

[H-K]

Your symptoms sound exactly like what I was experiencing with my timing issue on my GM TBI just a few weeks ago. Mine would idle rough, run rich, rev very slowly with hesitation to about 1800 RPM, then backfire and die. Timing was the last thing I checked because I "knew" the timing was already correct. Turned out the distributor clamp had loosened and the timing was off. Rotating that dizzy to 0-degrees took care of my problem. I think once you get your timing sorted it will probably fix your problem.

PS, you probably already know this, but with GM TBI, remember to disconnect the timing wire/connector while adjusting the timing, set the timing to zero, then reconnect the wire (if you can figure out a way to peek around that water pump).

 

[broncomitch]

Isn't that just with the GM dizzy or one that is able to adjust?

 

[B2-Bomber]

The EST needs to be wired up, with the GM distributor module mounted externally. I tried PM-ing you back, but your inbox is full. these are really, really simple. I'm happy to help

 

[broncomitch]

Okay, i cleaned it out.
I have the EST wired up and mounted on the firewall but it's hooked up to a stock duraspark dissy.

 

[B2-Bomber]

OK, so you have the pickup coil of the Duraspark wired into the GM distributor module? Thie Gm module is mounted on the firewall? My money says that you don't have it heat-sinked enough, and it failed. they start running rich as crap when that happens. It doesn't take long either. I have seen improperly heat-sinked modules fail in a couple of hours of driving

 

[B2-Bomber]

that's because the GM distributor module takes the pulsing of the distributor, and turns it into a square-wave 12v signal that the ECM counts each wave, and fires 1 injector every (2) pulses (that way both injectors fire once each per revolution). when the module fails, it sends intermittent/sporadic pulses that the ecm takes as the engine revving waaaay to high, and triggers the injectors as if the RPM is higher than it is.

 

[broncomitch]

You sir are very bright.
Not sure if that's my problem but the injectors seem to be doing that and this is a old module that I dropped a few times lol
So I'll go buy a new one on friday..
I didn't put a heat sink on it, figured the fire wall is cinda away from the heat.
Should I just go with a different ing setup?