Build 1985 FJ60 Gets a Holley Sniper EFI Setup

[wngrog]

Go to this screen.

Start at home.

Hit Monitor.

Hit Multi Gauge

Hit sensors.

This way you can see Duty Cycle. All the good stuff is on this page

 

[slh123]

Why is it at 1235 RPM?

when it starts it idles a bit higher for a couple seconds then settles down to about 800 RPM. Don't think this is connected to my problem, not sure though

 

[slh123]

Go to this screen.

Start at home.

Hit Monitor.

Hit Multi Gauge

Hit sensors.

This way you can see Duty Cycle. All the good stuff is on this page

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The first pic is before thee car starts and the second is while it's running before it dies

 

[wngrog]

How much time do you have on this setup?

 

[slh123]

How much time do you have on this setup?

A little over a year

 

[slh123]

If I changed the ignition module with a different module (not the same part but another GM 4 point module), could that be causing this problem?

 

[wngrog]

If I changed the ignition module with a different module (not the same part but another GM 4 point module), could that be causing this problem?

I have 20 or so DUIs (real Davis Unified, not a Chinese) and have never had any of them lose an ignition module. For you to lose two is where I would start looking

 

[TheDurangoKidd]

Show us where the hose connected to the base of the Sniper goes please. That second pic doesn’t really help. The hose between the PCV valve and “[that] thing on the intake manifold” is correct. Factory EGR/PCV location on the intake. The EGR has been closed off just like I did with mine. Looks like yours is welded shut with a bolt in it.

Thanks for the reply, sorry for the incredibly late reply. Work and then life got in the way of working on the truck. The hose at the base of the Sniper goes to the charcoal canister.

 

[BlackCat]

Still having issues with cold start lean spikes. Sometimes it’s fine, most times it’ll lean spike and sputter and recover. I’ve meticulously smoked the intake for vacuum leaks and made 2 exhaust side pre-O2 sensor leak repairs with no real change. A screen shot from a datalog last night shows actual AFR vs commanded AFR and you can clearly see it spike. It will occasionally do it when it’s warm too, but 95% of it is on cold starts.
Obviously seeing it on a graph is one thing, but I can’t really find an input other than condemning the 02 sensor without seeing voltages that jump out as a problem. No other inputs that I’ve been able to find dip with the lean spike. Everything stays steady. Anyone have any insight?

 

[wngrog]

I’ve got one that does the same thing and I’ve not found an answer. Runs great 98% then sometimes will do it warm. Most always does it pre 165.

 

[BlackCat]

I’ve got one that does the same thing and I’ve not found an answer. Runs great 98% then sometimes will do it warm. Most always does it pre 165.

exactly what mine does. I'm assuming a new O2 sensor won't fix it and I'm not one to shoot the parts cannon at it. Sometimes it'll cold start perfectly fine so it's leading me to believe its a sniper issue and not a vehicle issue. Obviously being desmogged takes a lot of possibilites out of the equation for intermittent faults.

 

[wngrog]

exactly what mine does. I'm assuming a new O2 sensor won't fix it and I'm not one to shoot the parts cannon at it. Sometimes it'll cold start perfectly fine so it's leading me to believe its a sniper issue and not a vehicle issue. Obviously being desmogged takes a lot of possibilites out of the equation for intermittent faults.

Every time I think I can blame the Sniper it always ends up being an input.

 

[Zjohnsonua]

Still having issues with cold start lean spikes. Sometimes it’s fine, most times it’ll lean spike and sputter and recover. I’ve meticulously smoked the intake for vacuum leaks and made 2 exhaust side pre-O2 sensor leak repairs with no real change. A screen shot from a datalog last night shows actual AFR vs commanded AFR and you can clearly see it spike. It will occasionally do it when it’s warm too, but 95% of it is on cold starts.
Obviously seeing it on a graph is one thing, but I can’t really find an input other than condemning the 02 sensor without seeing voltages that jump out as a problem. No other inputs that I’ve been able to find dip with the lean spike. Everything stays steady. Anyone have any insight?

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whats IAC % and commanded fuel mass doing at this same time?

 

[BlackCat]

whats IAC % and commanded fuel mass doing at this same time?

IAC at the time of the lean spike is 100%. It goes 100% at approximately 6 seconds into a cold start and remains there thru the duration of the log, which is 18 seconds.

I will say that overlaying after start enrichment over the AFR that after the enrichment lowers down to approx 100% after about 13 seconds is when the lean spike begins. I’ll try extending the after start enrichment some and see what happens.

Edit- I’ve made so many repairs and adjustments over the last few months to both the sniper and the truck. I just reset the sniper and will start from scratch.
If anyone has a seemingly perfect tune in their sniper and they’d like to send me the file to try I’d appreciate it.

 

[DrRock]

Give me a shout. We modify an inexpensive off-the-shelf adapter so that it sits on the FJ60 carb insulator, which is perfect for getting the height to clear the manifold studs and also acts as a heat shield for the Sniper computer. Comes with all mounting hardware.

I try to keep new carb insulators in stock too.

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Hello Cameron, FYI the plate I received with my kit from you was possibly fly cut on the top just a bit too much so the heads of the m8 screws are proud by around .5mm (.020”). Not a big deal as I just used some DIN 7984 low head fasteners but wanted to let you know. It could be that the counterbore for that fastener isn’t held to super tight tolerances too since it’s cast.

Cheers, James