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Topic: '88 5.0 starting/running problems (Read 12906 times) previous topic - next topic

Re: '88 5.0 starting/running problems

Reply #60 –
Quote from: MasterBlaster
Of course, hooking up a pressure gauge to the test fitting on the fuel rail would tell you that right quick. I have one on the shelf about 3 feet from me, but you're not exactly local.  ;)  Any parts stores nearby with a loan-a-tool program?


We have AutoHole, Advance/Discount, NAPA, and I don't know who else, if anyone. I mainly go to AutoHole because the rest are a couple miles further down the road. (except after the hurricane, when AutoHole literally had a hole in the front of the building about the size of driving two freight trains through the front door)

Re: '88 5.0 starting/running problems

Reply #61 –
Alright.. I decided to borrow the IAC from the LSC and hook it up.

The car will start with the replacement IAC connected.. but it's very difficult. Sometimes takes 10+ seconds of cranking. (it did that before with the other IAC, it could be that I just didn't push it hard enough to try to start it.. I have battery issues with this thing, so I don't like to risk running it down again) It acts just the same as before, needing to be revved a lot after first startup.. but now it will idle for a few moments when cold and then stall when the temp. gauge is reading only maybe 2 bars. (before it needed to get to 3-4 bars before it would idle at all)

Re: '88 5.0 starting/running problems

Reply #62 –
Dude, I think your fuel pump is dying. Look at the symptoms:
- Long starting times
- Erratic idle
- Fluctuating RPM's
- Pushing the pedal to keep it running/idling

Those are classic indications that the fuel pump is on its way out; that's what my gut says. I've been following this thread for awhile and chose not to introduce anything until my suspicions were confirmed. The long cranking time sealed the deal for me. You absolutely need to get your fuel pressure checked.

Re: '88 5.0 starting/running problems

Reply #63 –
And here I thought you were just reading it to make sure I wasn't g anyone off. :p

Alright.. but , $75 for a new pump plus $9 for the strainer, according to AutoHole.. this may have to wait until I'm done paying for the LSC.

I'll see what I can figure out as far as getting a pressure gauge onto it for testing.

Re: '88 5.0 starting/running problems

Reply #64 –
Quote from: Bird351
And here I thought you were just reading it to make sure I wasn't g anyone off. :p


Actually you've been behaving quite well. ;) Whenever there's a tech issue posted and it goes for more than 2 pages, there's a fairly serious problem somewhere. Your feedback and observations have been impeccable. Wish everyone was so observant...troubleshooting would be a hell of a lot easier then.

Anyhow, it's unwritten law around here to never, ever, EVER recommend parts store fuel pumps unless you love dropping your tank every few months/year to change out the pump again. They're just plain teh suck. For the same amount of money you can get a much better aftermarket pump (Walbro, BBK, etc) and not have to worry about it again.

First things first though...don't worry about the pump until you can confirm that your pressure is low. Priority one is getting the fuel pressure checked.

One more question: does the pump sound fairly loud or noisy? Sometimes they get louder as they die, sometimes they don't. Just another thing that could confirm that it is the pump.

Re: '88 5.0 starting/running problems

Reply #65 –
Ya know, I don't think I've ever actually heard the fuel pump. The pump on my '86 (the CFI car) is more noticeable.

When you have far more money than time, you have no excuse NOT to be observant about the car. Like I was just telling Shawn.. if I had gone ahead and replaced the IAC with a new one, I'd be set back $50 and still needing a fuel pump. But, I found a way to test it for "free", (if you can call $800 for another car "free".. but it's a f'n Mark! heh) and gave whatever updated observations I could. I don't feel bad about replacing the coil, cap/rotor, and battery terminal. Between the cap/rotor, coil, and re-gapping the plugs, it did make a noticeable improvement.. and the old negative terminal was just falling apart anyway. Don't feel bad on the TPS either.. the old one was reading 5v across the green and black wires. The replacement TFI had nothing to do with me.. my friend broke it, and he was good enough to replace it at his expense. He even went and picked up a deep-socket 7/32" to help get it off there.

(I ended up getting not only a new TFI, but a new Craftsman 1/4" drive ratchet out of it, because he was going to give me an extra one from his stock.. but then found a broken one he could take in and exchange, and I got the new one.. , this HAS been a good week! hah)

Re: '88 5.0 starting/running problems

Reply #66 –
K, I have a lot of friends who own Mustangs, most of them hatchbacks, and they can always hear their fuel pump running. I'm used to that. Our cars have an actual trunk, insulation, trunk liners, etc. because they were just a teeny tiny more upscale. :) So to hear the pump run on a T-Bird/Cougar you have to open the door, preferably in an enclosed area (garage, parking deck, etc.) for the echo, but if that's not available, at least on pavement or in a parking lot. Put your foot on the door light switch, turn the key forward but don't start the car. You should hear the pump whir for a second or two. It should be audible but almost barely so. If you hear it loud and clear, it's going south.

Re: '88 5.0 starting/running problems

Reply #67 –
Well, what I mean is, I've probably heard it at initial KOEO like you describe, but I haven't heard it over the engine. I HAVE heard my '86's pump while it was running, though. The two cars are parked nose-to-nose.. so the environment is essentially the same. (in other words, it's not a case of one's in the garage and one isn't.. I have no garage) And, just as a footnote, I never close the door on the '88 when I'm running it.. except that one day I "drove" it (let it idle in gear) around the yard.

Re: '88 5.0 starting/running problems

Reply #68 –
How about this one?

Re: '88 5.0 starting/running problems

Reply #69 –
That'll work. When you shop for them, you will only need the pump and sock, NOT the whole assembly. Sometimes they're sold complete for Mustangs...those will not work in our tanks.

Re: '88 5.0 starting/running problems

Reply #70 –
I'd probably just order that right there. AutoHole wants $75 for a pump, if I recall.. plus close to $10 for a new sock. Might as well just get the Holley.

Re: '88 5.0 starting/running problems

Reply #71 –
You could swap the LSC tank onto the Tbird(yea its the same except for the gage sending unit, I've done it) (actually I'm kiddin on the swappin part).... OR maybe you should swap the HO into the Bird and the SO in to the Mark......then just "default" on the LSC. :evilgrin: (kiddin again)

Re: '88 5.0 starting/running problems

Reply #72 –
Yeah, I know I could do tons of screwy stuff with these three things sittin' out here together.. and I've thought about it. (things like putting the HO in the '88 and putting the oft-discussed supercharged EFI 300 in the Mark for the "ultimate road trip car" project) But I think that, barring any catastrophic damage to any one of them, I'm going to try not to favor one over the rest too much. I'm just glad to have all three.

In all this, I've only ever cannibalized one car over another twice.. and in one of those cases, I bought a replacement part (coil) later on anyway.

Re: '88 5.0 starting/running problems

Reply #73 –
Well, I'm still stuck with this one, mainly because I can't afford to do shiznit with it until this Mark is paid off.

However.. it came up again with a different local friend about cleaning the injectors. In his words, just tossing them into a coffee can full of solvent (I forget which, might've been paint thinner or something like that.. it was very late at night when we had this conversation) and forget about 'em for a day.

What I want to know is, would this be a complete waste of time or even damaging to the injectors, or is this something I should probably do while I'm waiting for a more favorable financial situation to deal with possibly replacing the fuel pump? (after I test pressure, of course)

My other local friend (the one that busted the TFI and replaced it) is coming over today to finish what he started as far as setting the timing. Once that's done, aside from more cleaning, there's really not much else I can do to the car aside from something like soaking the injectors like that.

Re: '88 5.0 starting/running problems

Reply #74 –
Quote
What I want to know is, would this be a complete waste of time or even damaging to the injectors,


I'd deffinetely replace the o-rings after that.  Thinner has a way of hardening rubber.
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!