Hi Any One using Holley's sniper EFI? I have been fighting with it since may and not getting good results. My 455 has 25cc forged pistons I'm running stock 73 heads, a TA 290-94H cam and a edelbrock performer Buick 455 intake. Holley's tech guys have been trying to help as well but we are not making much progress. I am also running a MSD Distributor and have the Holley system running timing control. It starts, idles and cruses ok but it awful at W.O.T. I wont even squawk the tires off the line and can barley pull past 4000 rpm. Any experience is appreciated.
I would try getting it running without their timing control and see if it works any better. Next I'd see about running an open spacer under the throttle body as a lot of the TBI injection units don't like dual plane manifolds. Assuming the idle is good you probably don't have any o2 leaks but you ccould have poor fuel delivery from an old cruddy tank or weak voltage to a pump that can't keep up. The list will go on and on but there is a ton of info in the hi tech area about 4 forums below this one that's already been written.
The dual plane intake is a very good point, some throttle body fuel injection systems simply won't run well with a dual plane. I would also disable timing control, there are a few instances where Holley says timing control will not work very well with an MSD distributor. Holley feels it causes too much electrical interference to get accurate crank and cam timing signals. This is the reason why I ended up doing a coil near plug conversion using a Grand National Cam sensor and a custom crank trigger.
Thank you guys. I have a 1" open spacer on it. The fuel pump it supplying 68 psi even at W.O.T under load. We had the same trouble before timing control was installed with the factory points distributor. Holley asked me to connect the timing control in order to make sure it wasn't an ignition problem. The fuel tank is like new inside and out only about 5-6 years old. I installed a Holley in tank retrofit pump and sending unit. The sniper wiring harness it supplying the power source directly to it. There are not any O2 leaks that I can find. The plugs look quite lean. Holley said an exhaust leak typically causes a rich condition. I have new Taylor wires new MSD Distributor and coil. Holley says their engineers are working on it but have not given me anything to test in 2 weeks now. I have a sent a bunch of data logs and also the global configuration file. The tech guy said he can clearly see the symptoms in the data log but can not understand why its doing it. I din't try to cheap out I got all the parts Holley recommended to work together. I will look over the Hi Tech area as well Thanks again
no idea whats going on but - it is well known that BBB's LOVE cfm and higher fuel delivery under WOT.
Wild guess: Have you ever spark-tested the coil? A spark tester costs perhaps $12. Most MSD coils are known high-failure, Made-In-China items. I've owned coils that were partially-shorted inside; they'd spark at low load, but under high load they'd misfire. There's a dozen kinds of spark testers. This is my favorite style. Get the version for HEI systems if you aren't using a ballast resistor in the coil + harness. These are getting harder to find because the spark is exposed. The newer kind enclose the spark in a plastic dome so you can't get zapped. The HEI style uses a recessed center electrode, making a longer path to ground. The standard style has a normal center electrode.
I own a Holley Terminator system and the timing control can be used only with a small cap HEI (computer controlled HEI) or Ford TFI, so I can't use the system for timing control. Sounds like they enhanced that feature so it will work on other distributors, in theory anyway. If Holley only made a Dual Sync EFI Plug n Play distributor for Buicks. They make one for Pontiac, Olds, Chevy, Ford and Mopar but not Buick. Very frustrating. Just curious, have you locked out the MSD distributor and if so how many degrees advanced is the timing? You say the Holley ECU is supplying power directly to the fuel pump. You should use the ECU to trigger a relay that supplies full battery power to the fuel pump unless your fuel pump draws less than 15 amps. Is it possible when doing the initial set up you accidentally set the rev limiter to 4000 RPM?
The distributor is locked out. I set the timing to run 12 deg at idle 42 at cruse and 32 at w.o.t. and I set the static timing to confirm what the ECU is telling it to set the timing to is correct. The sniper wire harness has the fuel pump relay already in it. The preset rev limiter is 20 000 i set it to 6000. As far as using the MSD with the sniper system the harness is prewired to be plug and play with the msd pro billet Distributor and has its own coil driver so you don't need an MSD box. I originally had the sniper running without timing control. Just my factory points distributor and coil. The car ran exactly the same then as is does now. Holley suggested I install all the ignitions items as I had already purchased them and they wanted to eliminate my old ignition system as the source of the problem. I think the problem has more to do with the throttle position then the RPM. If i go past 1/2 throttle even from idle it bogs out the same at it does when you punch it on the hwy. I hope Holley comes up with something soon! its been over 2 weeks they have been telling me that the engineers are working on it. And they have been asking me to test things like the items you guys are asking since about mid June.
Going back to the TPS, did you put a volt or ohm meter to it(can't remember what setting the meter needs to be on to measure that) to see if the TPS is defective? It sounds like you aren't getting the fuel you need after 4,000 RPM and doesn't the TPS tell the confuser to add more fuel? Sorry if I might be way off here, electrical stuff isn't my expertise. GL Derek
I will ask Holey what the test specs should be Monday and check that out. But the hand held display is showing the TPS Position and seems to be accurate with where my foot is.
You'd know if the TPS was bad when watching the gauge and using your foot, no need to ohm it unless the gauge is jumping around indicating a short or failing unit. Sounds to me like a MAP sensor or VE table problem since it ran the same on the points ignition setup.
With the help of T/A performance and the FAST efi rep who they often work with I think we found the issue with my sniper system in only a few min. Only 3 of the 4 injectors are working. The driver side front injector is not spraying at all that can be seen visually while the other 3 are spraying lots while the engine is cranking.
No fuel spay in one of the bores huh? That sounds like a familiar suggestion cough cough... (Please see your other thread in hi tech forum). So is it a bad injector, clogged injector or something electrical just not firing the injector? Have you tried swapping the injector to see if the problem stays with that bore or follows the suspect injector???
Sorry Ken. When I check it with the vacuum of the engine I couldn't tell one was any different then the others. They had me prop the throttle body up off the intake on the studs and put some cardboard under the throttle body. Like this it was clear 3 bores flooded with fuel one stayed dry. Also it was clear by the fuel spray pattern on the cardboard. As far a swapping the injector. The unit is new not sure what it will do to my warranty if I open it. Not to bitch but I don't expect Holley to be any more helpful now then they have been for the last month.
Holley wasn't very helpful but my dealer stepped up had me return the unit and sold me a Fitech system. Thank you so much to Performance Improvements Barrie! for not letting Holley drag this out on me any longer. I also owe a thanks to Ken W, all of you for your help, T/A performance Tim and Bob Ream. Now I just need to install the Fitech. Fingers crossed.
Being a Bowling Green, KY person, the home of Holley, I'm disappointed in the service Holley provided in the face of overwhelming evidence it was not working properly. Once you are up and running with the FItech, I would be interested in hearing how the two systems contrast to each other.
Fitech is running! Had some trouble on start up. The software version in my unit was an outdated version. If anyone is installing a Fitech and it pops out the exhaust on deceleration, backfires out the throttle body, and is hard to get started good chance you have the old software. I can send it to someone who knows how to post the file on this forum if that possible. Could save you waiting on the tech support line or if you need it on off hours. Once I got the New software, the IAC set up. I cleaned all the wire harnesses up and went for a test run. It pulls hard again!! I think a little better then with the carb. Way better then the 3 injector sniper but that's not a fair comparison. The differences in the Kit? The sniper's hand held screens I think are better but I think the Fitech hand held feels more solid and they provide a suction cup mounting bracket thing sniper did not. The IAC is way easier to set up on the sniper. It only has 1 adjustment screw while the Fitech has 2 one for the front 2 barrels and one for the rear and the fitech it way touchier. The smallest adjustment was needed at a time to dial it in. Sipper comes with good quality wire loom and heat shrink electrical ends for you to make your connections to the car with, a relay in the wire harness for your fuel pump, a few different throttle cable brackets and an air cleaner stud. Oh and the Fitech takes a 5/16 stud where the Holley takes a 1/4 like my Edelbrock carb did. Fitech doesn't send any of this. If you are using timing control the sniper requires you to wire in a supplied coil driver. Fitech doesn't. it simply plugged in to my MSD pro billet. The wire is a touch short for our Buick's with the distributor on the front but it will reach. The sniper was way easier to sync the distributor with. It has a static timing setting in the hand held to do it. Set it at 15 set the distributor to 15 with a timing light and you done. The fitech doesn't have this feature so it keeps adjusting the timing on you while your trying to set it with the light. They tell you to rev it to about 2000 rpm and mach the deg in the hand held to the light but I only have 2 hands and struggled to get it right on. In fact I am sure I need to go back and tweak this again when I have someone to give me an extra set of hands. All in all I don't think one is a lot better then the other. Had my sniper been a good one from the start I am sure I would have been happy with it. and if you plan to add a power adder the sniper will do it at a lower price then the Fitech. The Fitech seems a bit beefier then the sniper. Overall its heavier I noticed putting it on the intake. Servicing the Fitech looks easier too. For example I think I could change an injector myself where Holley told me I couldn't because I would be required to disassemble the unit and it would void my warranty. The old software is T198 THE NEW SOFTWARE IS T198i
I didn't take any during the install. By the time the weekend rolls around I try to avoid my cell phone like the plague. I will take a few post pics.
