Fuel Injectors...

[maximos]

Well I think my injectors are going bad on me. All the signs are there -- hesitation (which gets worse the hotter it is), MPG is decreasing...I've been looking around for some replacements and I don't really know which ones to go with. I could go with the OEM injectors but the cheapest I have found them for is $50 each. I've also seen sets of them but they all say "high-flow" and aren't recommended for stock engines. I have an essentially stock Cobra engine. Anybody able to find a good replacement for OEM?

 

[95Vert]

WTF?!?!?!?
$50 each. Where have you been looking? Go into the classifides and you'll find 19lb inj. up to infinity lbs for a decent price. And by decent, I mean less than $200.

 

[Swarzkopf]

Eh...

Generally, fuel injectors aren't the first thing to check on when your stock GT feels a bit down on power and has some hesitation. If you've got high mileage on them, try running some fuel injector cleaner through the gas.

Has your car been tuned up recently? What do the cap and rotor look like? Spark plugs/wires? How about the air filter? Fuel filter? Cleaned the MAF lately?

This is stuff I'd look at before assuming that a/the fuel injector/s are going...

 

[maximos]

Well first thing, it's a Cobra...Second, everything you suggested to check first have already been inspected. Plugs, wires, filters are all only months old. The only thing that keeps me coming back to the injectors is the difference in performance when it's cold out compared to when it's hot.

 

[95Vert]

What do you mean, "It's a Cobra". Doesn't matter if it's a Saleen, inj. are inj. and they aren't that expensive.

 

[95Vert]

A bad dizzy could do the same. Check that out. Have you check the module and coil?

 

[urban96]

you looking for 19lb or 24lb inj? i have some 19's collecting dust...

 

[95Vert]

Probably 24s since it's a cobra.

 

[mo_dingo]

you looking for 19lb or 24lb inj? i have some 19's collecting dust...

He has a cobra = 24's...

I can't see fuel injectors causing bad gas mileage. For one, your plugs would be turning black from running rich, which I assume is not the case since you changed them recently and inspected the plugs thoroughly. Secondly, if they were clogged, you would be running lean, which would make all your plugs white and you would be detonating.

To start with, is the car running rich/lean or stoich according to the plugs? Have you checked for codes (even with no MIL you could still have codes stored). Have you cleaned the maf/iat? Have you cleared the KAM and let the computer relearn the car?
Scott

 

[urban96]

ah, ok. i seen this and wasnt sure

I have an essentially stock Cobra engine.

i agree on checking plugs and cleaning maf

also no one has suggested or mentioned your O2 sensors? are they still stock? how many miles? might be time to replace them

 

[maximos]

What do you mean, "It's a Cobra". Doesn't matter if it's a Saleen, inj. are inj. and they aren't that expensive.

Cobra was meant to distinguish between the 19's and 24's -- Different parts on different applications can obviously act differently. And go ahead and give Ford a call and you'll see how expensive they are. I very reluctantly trust aftermarket parts.

I plan on replacing the O2 sensors within the next week, they're pushing 100,000 miles. I figured this weekend I'd go ahead and do the O2 sensors and the injectors (if I can find a good, reliable set at a decent price).

As far as the distributor, what should I be looking for? And, nobody has told me where I could find a set of injectors, anyone buy some recently?

 

[WhiteCobra95]

How many miles are on your Cobra? I would suggest a compression and leakdown. Also, you could try replacing your O2 sensors if you haven't already. (They get lazy over time and can cause the ECU to adapt the fuel trim incorrectly.) If you've ever run a K&N filter, you could try cleaning the MAF element.

Good luck man, whitecobra95

 

[urban96]

ebay/corral

 

[Swarzkopf]

And, nobody has told me where I could find a set of injectors, anyone buy some recently?

Because it's probably NOT your fuel injectors causing you problems...but if you insist on spending money on injectors, Summit sells sets of 8 pretty reasonably.

 

[Swarzkopf]

About the 02 sensors- from my understanding, they'd cause hesitation/power loss at part throttle only. At WOT the ECU gets all of it's input from MAF/IAT, correct?

 

[95Vert]

Cobra was meant to distinguish between the 19's and 24's -- Different parts on different applications can obviously act differently. And go ahead and give Ford a call and you'll see how expensive they are. I very reluctantly trust aftermarket parts.

I plan on replacing the O2 sensors within the next week, they're pushing 100,000 miles. I figured this weekend I'd go ahead and do the O2 sensors and the injectors (if I can find a good, reliable set at a decent price).

As far as the distributor, what should I be looking for? And, nobody has told me where I could find a set of injectors, anyone buy some recently?

It's not called a stealership for nothing!

Swarz, you are right. The o2 are disregarded at WOT.

 

[Mustangless]

have you checked to see if there are any codes?

 

[95Vert]

We're trying to help you avoid spending $200 and finding out that's not your problem. But if you're not willing to listen, just go into our classifieds or corral's and you'll find plenty there. Good luck.

 

[maximos]

I already said I have checked everything you mentioned and that I was going to replace the O2 sensors. That's why I keep wanting to go with the injector issue. However, because I respect you guys immensely, I'm going to give the entire thing another run through and see if there was something I might have missed before. I might just give it another tune up for the heck of it, it's not that expensive to do anyways. Before I mentioned that when it's hot out is when it seems to happen the most, is there something linked to that aspect of the issue?

Someone also mentioned that the distributor could be the issue before, what should I look for there? That's the one thing that I haven't checked.

 

[Swarzkopf]

You never said you cleaned/checked the MAF and IAT...DEFINITELY do this.

Considering your recent tune up, in your shoes, I'd probably:
1. Clean the MAF. Search for how.
2. Pull the codes.
3. Check the condition of your spark plugs. (And if your pulling your plugs to look at them, you might as well check cylinder compression while your at it).
4. Run a bottle of fuel injector cleaner.
5. SeaFoam the engine.

I'm always suspicious of the MAF on our cars...dirty/bad MAFs seem to cause so many problems for so many people.

I take it you replaced the PCV when you tuned it up?