Hello folks, what table does the 7747 use when intering closed loop? I'll post specs and such later, but my problem is, the engine dies the instant closed loop is flagged. Runs very well cold, as you can expect I'm a noob..but learning. I should add I'm using the $42 xdf... Perhaps my question should be, what is the natural progression from open loop to closed loop?

Thank you,
Medivh

 

What happens to the INT and BLM when it enters CL?

what does the NB02 mvolts look like when this happens. Is it swinging nicely?

Is your IAC functioning? Does it appear dirty? Lack of IAC function may cause that.

Do you see a CE/SES light? If none check for codes as well.

It appears you are going very lean at that entry to CL. What is your FP?

 

Thank you for your response, I realize now my question was pretty vague.

My specs are as follows > 402 bbc, stock heads with 2.19/1.88 valves, Headers, mild cam forget specs seems like it was a r/v type cam. Stock compression. Tbi has been donated bye a 1988 chevy 5.7 truck. I'm using the E2000 inline fuel pump, My psi is steady @ 15 pounds, Ive bumped the BPW up to 127 also. Now for your questions>

1) Int/Blm are low so I'm very rich 97/108 range I need to get that under control

2) NB02 mvolts "3 wire heated" 900+

3) IAC hovers around 60-100 kinda high

4) no codes at all ses appears normal "it does work"

5) I idle in the 50 map range 750 rpm "dies under load between 1200-1800 rpm" This is also when I notice c/l I have winaldl and a auto x-ray hooked up

In conclusion I Think I need to get my blm under control and iac first then worry about the rest? I can burn my own chips I use the burn 2 and tuner pro.

The bin I'm trying is AZFT with the $42 xdf On a side note over the weekend I did the math and got my blm in the 50 map range on target, These numbers seemed very low to me and would lean out with any throttle. Perhaps i need to lower my BPW? Maby use a 350 VE table? At any rate back to reading alot more

 

It appears your BLM is at its rich limit. No more correction can be had. 350cid with 55 lb injectors and 15 FP pressure. I show 141 for BPC. NB02 V are as expected, rich to max. IAC should be 5-20. tables are OK for any CID. Idle 50 MAP? That does not seem right unless a large cam. 30-40 seems where it should be. 50 MAP puzzles me.

 

Something I was thinking about last night about the map, when I give it throttle the map does not change stays at 50 this makes me think I should check it out, I would think it would move with manifold vac changes. I shall try and get some data logs posted over the next few days along with my bin. Thank you for your reply

 

Well would seem ive been chasing a bad part making it hard to tune. I checked my map sensor and it stayed between 1.86-1.90 volts key on engine off with me giving it 5-25 pounds of vacuum with the hand held pump.

 

bad luck key on engine off should be 4.7-5.0. full vac maybe .50-1.0V

 

And is your MAP hooked to center vacuum port on rear of TBI unit?

 

Got a new map and the engine runs much better, however over the weekend my chip died or my burner so im on hold waiting for new chips

 

Well after a dead map sensor,chip, and three spark plugs my 402 BBC Tbi conversion is complete. Engine runs 200 times better than it did with the carb, truly a joy to drive Wanted to thank Ronny and the others for helping me out. Next is a tpi conversion in the 78 camaro