70k10tpi

Ok guys here it goes i bought fast's ez efi reto fit tpi system and i can not get it to run properly. If i go more than a quarter throttle from a stop the motor bogs or dies. If i punch it in park it dies. Ecm is good according to fast as i sent it back. All the sensors are brand new. Tach input signal is coming from a msd box which is recommended. No vacuum leaks and the 02 sensor is located in the header collector.i have high impedance 30lb python injectors, summit efi fuel pump and mallory adjustable regulator. Now i did turn down the acell fuel control on the handheld which helped a little but not enough. And the a/f readings at idle are all over the place. Also the wiring for the unit is routed away from noisy components. Im totally lost here. The motor is a 350 with double hump heads 2.02 1.60 valves,9:1 cr, headers, and a small voodo cam 254 idle - 5000. Any input is tremendously appreciated.

sofakingdom

iTrader: (1)

Sounds like ENTIRELY too much injector.

Try some 24 lb ones. Snarf some used Frod light-blue-top ones (you can get em for around $40 a set) off of fleabay and see what happens.

70k10tpi

Yeah i was thinking that too. I would have thought the self learning system would have compensated for injector size but maybe ur right they might just be to big to handle. Still puzzled why the af ratio at idle started bounceing all over full rich almost to full lean where as it was pretty constant before right at 14 in park.

70k10tpi

Ok so the ez efi runs 4 85lb injectors for a totall of 340 lbs and the 8 30lb injectors i run would be 240. How are they getting these things to run on 290hp stock motors all the way to 550hp. This is confuseing the hell out of me. I have smaller injectors ill give a shot ive tried every thing else exept for running the 12 volt switched to a toggle instead of plugging it in to my factory harness.

Tony89GTA

iTrader: (7)

Your injectors size is fine, 30lbs is not much but it does need to be tuned proper. I've ran 28lbs, 42lbs, and now 60lbs and my idle is great. You might have a exhaust leak that's messing with your a/f ratios. Have you checked your fuel pressure? Have you tried tuning your acceleration enrichment? I have not messed with the ez efi myself but I'm assuming it has something for that.

70k10tpi

Fuel preassure reads a constant 43psi and i turned down the acell fuel setting wich is like a acellorator pump in a carb to its lowest setting. I also put the 02 sensor in the collector of my header to make sure it was getting a good reading and everything is tight on the exaughst no leaks. At this point im about to throw it out the window. Ill give it one more shot then if that doesnt work ill go to the good ol tried and true factory gm computer with painless harness. Since im new to the tpi game how hard is it to get a good tune on a factory computer giving a compitent programmer my vehicle speciffics?

Tony89GTA

iTrader: (7)

Maybe you need to turn the accel setting up, what does the WB02 read when you quickly step on it? How about all of the other sensors, they all in check with your scantool?

BOSS 357

iTrader: (1)

Buddy, I feel your pain. I have the EZ too, been working with it on and off for two years now. I've just finally gotten around to seriously solving all the issues it's thrown at me and thankfully, this is the final issue. I also run the Multiport Retro.

At the moment, I am trying to solve a stumble out of 1st/2nd gear and am in need of a correct flow rating for my injectors.

My engine is a 357cid TPI. The values I have are:
IAFR 13.4
CAFR 13.8
AccFu -04

I have found that the EZ needs to give more fuel to run correctly. Also, the AFRs need to be somewhat closer together so when it switches from idle fueling to cruise fueling, there won't be that pause. You said your car is rich and bogging down? I'd make sure you have the fuel pressure & injector flow information correct in the handheld first. That said, I have also found that taking fuel out via the AccFu works best for my car; I had set it at 00 and +01 and that boggs down almost instantly.

I still get a chuckle when I read that it is "plug -n- play". Also try the FAST forum, they give good advice there too:
http://www.cpgnation.com/forum/fast-...t-support.html

70k10tpi

Tony89gta the system has a hand held that tells you if a sensor is bad and no eorr codes. Bought all the sensors new from fast also. Even pulled out the o2 sensor put fuel on a rag and covered it. Showed full rich when i did that and took it off full lean so i take it thats working corectly.Boss 357 the fuel pressure was good when i pulled the manifold off due to my frustrations had it set right at 43.I even cranked working up to almost 60. Each time i changed pressure i reset the computer to corrected specs. To further complicate my problem its not in a car its in a 1970 chevy pickup and its 4 wheel drive with 33inch tires so its already under a load from a stop making from what i can gather a over fueling situation worse. Now when i took the manifold off and slapped on my holley it started doing the same thing now that threw me off for a muinet so i took the air cleaner off and the back venturies where just dripping fuel at a idle loading up the cylinders and the fuel injection had the same symptoms wich leads me to belive to much fuel. Now i manually enter som settings in and had it running almost perfect for about five muinets till the computer decided to tune its self back to **** mode. I also un hooked the iac for that five muinets it ran good. I cant fuigure out why this thing wants to run so rich i mean the motors pretty healty making a honest 325-350 at the fly wheel no ground pounder but enough motor for 30lb injectors i thought.

70k10tpi

Also thank you to every one for your input so far. Its greatly appreciated.

BOSS 357

iTrader: (1)

First thing is, if you swapped your fuel-injection manifold back to carb and didn't switch back to the lower pressure carburated fuel pump, that may be why your carb was so wet.

Your rich condition to me says incorrect info in handheld, wrong flow data for the injectors, an exhaust leak, faulty O2, or EMI. You mentioned everything is ok but no mention of EMI.

Go to the More Option/Info screen and tell me what your IRM value is (key on, engine off) 24 hours after you last shut the car off. Also, what are your IAFR, CAFR, and Accel Fuel values? Also, where did you route the harness, is it near any ignition equipment and where are the POS/NEG wire plugged into the battery? Wire routing is critical.

I'm no expert, just relying on my recent experience with EZ. I still suggest you make a post on the forum link I sent as well (since it's their product). You'll see my posts and frustration there too.

70k10tpi

@357 Boss Haha no pump came off i think the 60 psi pump might have been a bit much for my carb lol. But unfortunatly i cant get the imr or other numbers you mentioned right now because the system is off the motor. Turned the acell fule down to -8 wich seemed to help alot going down the road. That got rid of the bog when i got on it doing 25mph or up. Ran super going down the highway no problems their so good in fact it broke the drum where the input shaft goes to in my th 350 tranny lol. The problem is just at idle or takeing off. I hooked the system up as you mentioned to the positive and negitive side of the battery and tried to get every thing as far away as possible from noisy components.i did do some reshearch and found that they dont like hei distributors wich i have but i got the tach input going to the msd. Now would the hei still b a problem? Also im not useing some wires fan/ac from the ecm and read that they can act like antennas for electical noise.I found that out after i pulled the system off so i never got to try it.ecm is mounted in the cab so it should be away from noisy components and the only part of the wireing harness that goes any where near any thing noisy passes by the hei dizzy and goes under the manifold kinda unavoidable there. And yeah ur absolutley right i should shoot a thread to the other fourm too. Just thought u third gen guys would have a bit more experiance with the ez efi tpi retro fit system.

BOSS 357

iTrader: (1)

I think there are only a handful of us here on TGO using the EZ-EFI. I ran into a blizzard of haters telling me either learn to burn chips or get the more complicated XFI..which if I did that, I might as well burn chips. For some reason, having a computer tune by AFR was blasphemy. I must admit to those haters that it is not a simple "answer a few questions and enjoy the burnouts" type situation by any means either. Rant over

I have my harness under the plenum and the ECU is also mounted on the passenger side kick panel. EZ doesn't like any distributor or plug wire or ignition box, not just HEI stuff. My harness runs under the distributor and passes the plug wires twice or more. That is a good example of poor routing. I had to wrap my harness in several places with aluminum foil (double wrapped the O2 harness) and that brought my IRMs down from 07 to 00/01. As far as IRM goes, when you can get a reading, if it is more than 03, you may have an interference issue (although FAST has told me if that number is 10 or more there is a problem).

Your unused fan/AC wire is ok, I don't have that hooked up either and it's not an issue unless you have it sitting right next to your MSD box or something.

So that leaves your original problem which sounds just like the problem I'm fighting too. My car is manual and coming out of 1st/2nd is fine if I feather the clutch out; if I put my foot in it, it will buck until I clutch and feather. Funny thing is if I floor it, I don't have this problem. My O2 correction (1st screen with the graphs) will hit -10 to -25 meaning it's too rich. I have moved the AccFu up and down and moved the cruise fuel up and down and can't seem to dial it out. I have since been told to drop my fuel pressure (which seems like a band aid fix) or retard my timing (which doesn't make sense to me for the RPM band in which this is happening). I cannot verify the pressure at which my injectors were rated so I'm betting I have incorrect data entered into the handheld (which is why I mentioned that to you earlier). I am going to try and change my CAFR and AccFu again next week, if I figure it out, you'll know. There will be a ticker-tape parade here at the house.

When you get it all hooked up again, run the car and a day or so after you shut it off, get me the IRM value. Also, tell me what IAFR/CAFR/AccFu you are using.