Running seriously rich

[Hans]

Well, this is probably in relation to my various threads of 2008 regarding my stalling/no start issues last year.

Turns out that it seems to be running ungodly rich, to the point of causing poor idle and eventual stalls. I finally figured this out today by letting the truck sit still at idle until it stalled. Couldn't restart it, smelled seriously strong of fuel. Pulled the fuel pump fuse, and I was able to get it to run about 5 seconds with repeated shorter bursts of running. Put the fuse back in, and it started right up running fine.

So, now what? All the electrical side seemed to test ok in previous diagnostics, but I wasn't looking for something causing a serious rich issue at idle speed. I don't believe that the O2 sensors come into play until you come high off of idle.

Fuel pressure? Injector leak? Any way to even test for these on a '94 without having the injectors rebuilt and tearing apart the regulator?

-Hans

[imola]

sounds like leaky injectors, check to see if the pressure holds. Get it replaced asap as it will kill the cat. convertor. Don't both with rebuilt, new ones are pretty reasonable from various online sources. Plenty of other V8s use the same injector.

[Hans]

yeah, but how do you check the pressure in a '94? There's no fitting anywhere on this version fuel rail. The factory diagnostic test has you pull them all out and fit them on a test rig.

It seems that new injector prices have gone up a lot too. A couple years ago I was seeing them at $229 a set. Same site now has them at $329 per set.

[junkyddog11]

You can test fuel pressure leak down in line. You can check the injectors by making a test rig out of an old fuel rail or removing the fuel rail on the truck. You can also pull plugs and see which ones are soaked, or blackened.

Use Ford 5.0 fuel injectors. I think ECR has found something that s supposed to be better as Mike has had some issues with the Fords (?) but I have used them with great success.

[Hans]

Set of rebuilt ford injectors, and she's running fantastic again. I went with a set of 19lb injectors out of a crown-vic.

-Hans

[Hans]

The ones I got were Ford FOTE-D5A injectors. Number 280150943 and they fit like a glove.
No core charge. Almost every mid-90's Ford used them, nice and common.

Got mine from http://www.southbayfuelinjectors.info/catalog/
E-mail their sales rep Julie.

-Hans

[ini88]

looks like they just put them up on their site?

http://www.southbayfuelinjectors.info/catalog/advanced_search_result.php?keywords=280150943&sort=2a&page=2

[Hans]

Yep, that's the ones. But I believe the e-bay postings from them are usually a couple bucks cheaper.

-Hans

[cellulararrest]

Is there a noticeable performance increase with these?

[jaherring]

Thanks guys, that's what I needed!

[Hans]

Is there a noticeable performance increase with these?

Considering how bad it was running before, most definitely. I can actually use 5th gear at 50mph again and it starts a lot easier now. Definitely a lot smoother in the low end too. But I still have some lingering issues somewhere I think, I'm still getting a surging idle sometimes which I had hoped this would cure. I'm running out of parts to replace that don't use words like "block" and "valve". I was also due for an oil change, which I did today, so it's back to normal pressure again.

I'm eager to see the mileage specifically, but it takes me a couple weeks sometimes to burn through a full tank..... I'll update when I know for sure. Only about 30 miles since I replaced them, so it's too soon for a full report. I'm sure the cats need to burn a bit more crud out still too. The big thing for me wasn't really to get a performance improvement, though I'm sure it will get a bit more power under full-stomp, I was more concerned to getting it running smoothly again.... which seems to be successful.

-Hans

[cgalpin]

Awesome! I'd love to hear what this does for your fuel economy.

[Hans]

Well, good news and bad news. The injectors work great, but didn't solve my problem. I'm still having surging idle issue. Every fix I put into it changes how it runs, but never solves the problems.

So, after new distributor, injectors, O2 sensors, ECU, Mass Air sensor, stepper motor and coil, it no longer has the cold start problem. It also isn't over-heating anymore. But I still have that surging and stalling at idle.

BUT, and here is the good news. It's definitely an electrical gremlin somewhere that I can finally start tracing. I had a real oddball problem. With the ignition switch on, but the engine not running, something was causing the ECU to get a signal. This caused the fuel pump to come on, and the injectors to start firing. At this point, I'm suspecting I've got some bad diodes in the alternator.

Oh, and I also think I figured out what that little can attached to the coil was (that I got rid of when I replaced the distributor, coil and wiring). It's an alternator filter, intended to smooth the output signal. I'm guessing that I fixed one problem, but introduced another one (or uncovered, to be more accurate), when I swapped the distributor in.

-Hans

[rover4x4]

http://www.southbayfuelinjectors.info/catalog/product_info.php?products_id=37




Hans did you find your problem?

[Hans]

Just found it a couple days ago actually, and got it inspected today successfully. Ready for an odd one?

Bad diodes in the alternator were partially blowing out my ignition modules. But the issue was only showing up when hot. New alternator, e-spark module and plug wires..... and it's been fine for about 2 weeks now. The bad modules were causing the no-start and stalling issue. Bad plug wires caused the rough running and overfueling in a couple cylinders. There's also an alternate wiring setup now for Mallory distributors with the E-spark module, which also made a huge difference.

Of course the new Mass Air sensor, O2 sensors, TPS sensor, Injectors, etc.... didn't hurt I'm sure. Will figure out my new milage tomorrow when I refill the tank for the first full tank after the fix.

-Hans

[artm]

As the old commercial says...

...wouldn't you really rather have a diesel?

[Abrooks]

Almost identical to the issues I was having with my 94 nas. Turned out to be a bad regulator in the alternator that was frying ignition modules. Tach was fine, output appeared to be good, but it made the ignition system insane. That got expensive. Oh, the "can" thing is a "coil suppressor"

Glad you got it fixed!

[rover4x4]

You can test fuel pressure leak down in line. You can check the injectors by making a test rig out of an old fuel rail or removing the fuel rail on the truck. You can also pull plugs and see which ones are soaked, or blackened.

Use Ford 5.0 fuel injectors. I think ECR has found something that s supposed to be better as Mike has had some issues with the Fords (?) but I have used them with great success.


I would be interested to know. A lot of good info on the Ford Injectors here and other BB's. Any updates on ECR's injector research.

[Hans]

Well, now that it's running great, I can finally give a good estimate on the new fuel milage. Prior to all the work, I was getting around 10.5mpg out of it, 150 miles per tank would put me almost bone dry. Now I'm getting around 180-185 miles per tank, which I'm figuring around 13mpg now. Not a bad improvement at all I'd say, around 25%.

Though due to the timeframe, some of that has to do with the summer blend fuels at the pumps now. Still, it's the best mileage I've ever seen from the truck.

-Hans

[slowpoke496]

Hans,
I recently changed my head gasket to cure overheating problem. At this time I changed my injectors to 19lb Fords. Ran great for one week except I had surging idle particularly when coming to a stop. After week of trouble shooting i have found that cyl #1 is not firing the injector (checked with test light all other fire) and i have intermittent spark confirmed at cyl 1(did not check other yet, got too dark). Currently running Mallory Unilite Dist. I am going to change out the Dizzy back to stock tonight to see if it cures problem. Question is, Would bad alternator also cause #1 injector not to fire?

Any incite would be greatly appreciated.

Bryan

[Hans]

Hans,
I recently changed my head gasket to cure overheating problem. At this time I changed my injectors to 19lb Fords. Ran great for one week except I had surging idle particularly when coming to a stop. After week of trouble shooting i have found that cyl #1 is not firing the injector (checked with test light all other fire) and i have intermittent spark confirmed at cyl 1(did not check other yet, got too dark). Currently running Mallory Unilite Dist. I am going to change out the Dizzy back to stock tonight to see if it cures problem. Question is, Would bad alternator also cause #1 injector not to fire?

Any incite would be greatly appreciated.

Bryan

So it's just the one injector? They are batch-fired in a D-90, meaning that all the left side injectors fire at the same time. Same with the right side. So if ONLY that injector isn't firing, then the problem is in the wiring for that one injector. Any other issues would cause the other 3 on that side to also not fire.

Just double check that it is the right connector. IIRC, doesn't the fuel temp sender use the same type of connector, and is right next to injector #1?
-Hans

[evilfij]

Bryan, make sure the temp sensor and the #1 injector wires were not mixed up. You can hook them up wrong.

Ron

[slowpoke496]

Okay that was the problem! :blush Thank you!!! sometimes i guess you are just too close to the problem. Now I need to determine if the mallory unilite was the cause of the intermittant spark to cylinder #1. Got home too late finish changing out the distributor.

Guys thank you again and i will post back with the my findings on Wednesday.

Follow-up Post:

Hans,
I read that you have the E-spark unit over the Unilite what are the benefits. I found that it is cheaper is it also more reliable or robust?

You also mentioned alternate wiring do you have a link with that detail?

[Hans]

Yes, the E-spark is all of the above. Cheaper, more reliable, and more robust than the original versions.

The alternate wiring was a little "NOTE" blurb that was on the e-spark module instructions, I don't know if it would work with the original style unilite modules. Here's the link, and the direct quote out of it. I found it made a big difference in performance for me.

http://www.malloryperformance.com/pdf/6100M.pdf

NOTE—
If your vehicle is difficult to
start, remove the red wire
from the plus (+) side of the
ignition coil and connect it
to the ignition switch side of
the ballast resistor.

[slowpoke496]

Hans/Evilfij,

Thanks again! the mallory unilite module failed the test procedure with a credit card. Replaced it with the E-spark using alternant wiring as per your post. Engine turned over and started better than ever.

It appears that i had an intermittant ground that may have caused the ignition module to fail? I ran a new ground wire and added the power filter to the E-spark module.

Engine is running cooler and no longer running rich.

Cheers!

[Hans]

The original style unilite modules have a reputation for being very fragile things, and it didn't take much to cause them to fail. The E-sparks are supposed to be much more robust, while also being less expensive. The ground problem could very well have caused it to fail, and the power filter is extra insurance for the future.

-Hans

[rover4x4]

So the Mallory with the e-spark is the way to go?