4-hole VS Pintle-style injectors

[Darkwriter77]

Last year, I swapped out my stock 19-pound injectors because half of them were drooling fuel from the seams - apparently a problem with the 1989 model injectors. I scored a set of 8 four-hole style 19-pounders taken out of a '95 T-Bird with a 4.6L. It seems like ever since then, along with the notorious surge demon issues everyone seems to get at some point with any 5.0L, I had to deal with the Satanic Possession issue ... y'know, 1/3 to 1/2 power loss at WOT that would sometimes come back into full power like pushing a nitrous button, the occasional lumpy/surging idle, light backfiring out the exhaust during low-end grunts, surging at cruise, etc. (There's a HUGE thread on all that still floating around the archives, I'm sure.)

In spite of having changed out EVERYTHING under the hood but the motor, itself - and I mean EVERYTHING, the list of parts I've cleaned/checked/replaced is absurd - the injectors seem to be the only remaining possibility. Being that the car ran like crap before these four-hole injectors went in, it's been hard for me to say for sure that's the cause of my misery, but it never had the power loss/surging/backfiring crap until those went in.

So, to the point: Are these newer-style injectors really worth all the hype and claims that they're more efficient and whatnot, or would I just be better off buying a brand new set of FRPP old-school 19-pound injectors?

It seems to me that I've got an injector that's sticking open periodically, as all the symptoms are pointing to a rich condition. It backfires between the 1-2 or 2-3 shift at WOT and leaves a puff of black smoke, I sometimes pull trouble codes for "running rich" conditions, and since this crap seems to go in week-long spats, my MPG drops from the usual 18-19 city to 14-15 until things clear up on their own. I've read that one flaw of these newer-style injectors is that, if/when they fail, they sometimes stick open and just dump fuel, whereas the old pintle ones just plain don't squirt when they fail.

Anyone else had similar problems with the newer injectors and switched back? And anyone got a good set of old-school 19-pounders they wanna part ways with for cheap?

 

[dastang2]

not sure but i had a 95 v6 and put a motor from a wrecked 98 v6 into it and used the 98's injectors. it had a bunch of codes and didn't run like it should have for a long time until i swapped the 95 injectors in. it finally got rid of the codes and got all the power back. they had different part numbers as well.

 

[jrichker]

I have been running the 4 hole injectors for several years now and haven't noticed any problems. They came with the Explorer intake I am running.

I would do a cylinder balance test to see if any of your injectors are having problems.

Cylinder balance test:
Warm the car's engine up to normal operating temperature. Use a jumper wire or paper clip to put the computer into test mode. Start the engine and let it go through the normal diagnostic tests, then quickly press the throttle to the floor. The engine RPM should exceed 2500 RPM's for a brief second. The engine RPM's will increase to about 1450-1600 RPM and hold steady. The engine will shut off power to each injector, one at a time. When it has sequenced through all 8 injectors, it will flash 99 for everything OK, or the number of the failing cylinder such as 22 for cylinder #2. Quickly pressing the throttle again up to 2500 RPM’s will cause the test to re-run with smaller qualifying figures. Do it a third time, and if the same cylinder shows up, the cylinder is weak and isn’t putting out power like it should. See the Chilton’s Shop manual for the complete test procedure

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at Walmart.

Or for a nicer scanner see http://www.midwayautosupply.com/detailedproductdescription.asp?3829 – It has a 3 digit LCD display so that you don’t have to count flashes or beeps.. Cost is $33.

 

[RaceDvr50]

Ok you may have checked this but I had some power problems when I had my stock distributor. They have a problem with the pick-up going bad and it will intermittently drop the fuel pump. Do you have a fuel pressure guage that you can watch while you're driving? Or maybe another distributor you could drop in. I swapped up to an Accel billetech 10,000 RPM dist for under $200

 

[Darkwriter77]

I've already swapped out the distributor twice - once to see if it was, in fact, the pickup coil, and the second time because the reluctor magnet somehow popped loose and jammed inside the dizzy, leaving me stranded exactly a mile from my house.

I do have a fuel pressure gauge, but nothing I can mount up to monitor while driving. I have checked it out while it's doing the funky idle gig and when it's behaving nicely, and the fuel pressure never changes at all from the norm, which is why I'm suspecting the injectors and/or fuel pressure regulator. (Going to replace that, as well, while servicing the fuel rails, just so I don't have to take the thing off yet again.)

So, when picking up another set, should I stick with these four-hole units, or should I go with the old-school pintle-style injectors? I figure the cost would be the same either way if I score 'em from eBay again, I'm just wary of these four-hole buggers and their supposed ability to stick open...

 

[Black1987Stang]

could ur problem maybe be ur fuel pressure regulator? any updates on this

 

[Vinnietbird]

I'm also using the new style which came from a '96 Explorer.I just swapped them in when I installed my Explorer intake.I haven't had any problems at all.