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Topic: '88 5.0 starting/running problems (Read 13002 times) previous topic - next topic

Re: '88 5.0 starting/running problems

Reply #45 –
Don't know that I can get all of those readings. It just won't start with the IAC connected.

Re: '88 5.0 starting/running problems

Reply #46 –
Quote from: Bird351
Don't know that I can get all of those readings. It just won't start with the IAC connected.


Start it up and then plug it in...

Wonder if there is a chance the contacts in the plug are reversed??? Something has to be pulling the IAC closed, and since it is fed 12v on the red wire and lowering the voltage on the white/blue increases speed..... it just don't make sense....

UNLESS... Possibly you don't have a IAC or EEC problem at all, maybe its weak fuel pressure and its just so lean any extra air causes it to stall... That would also explain the problem with getting it to rev... There is a test to see how much fuel it can pump in a given time(doesn't require a fuel pressure gage). I'll do a little more diggin'.

Re: '88 5.0 starting/running problems

Reply #47 –
Should I just pick up a new FPR and try it? I think AutoHole listed $18 for one. I've heard they're a bitch to replace, tho.

Re: '88 5.0 starting/running problems

Reply #48 –
Never seen a F/P reg cause weak fuel pressure(although its possible), they usually cause high pres.

Re: '88 5.0 starting/running problems

Reply #49 –
OK, I'll keep looking for wrong trees to bark up, then. :p

This thing is making me feel like a royal idiot.. but hey, at least I haven't thrown a "I hate Fords" fit over it.. heh.
 

Re: '88 5.0 starting/running problems

Reply #50 –
Quote
Never seen a F/P reg cause weak fuel pressure

Doesn't that happen if the diaphram inside the regulator brakes?  A buddy of Mine has an 82 Malibu with a 383 TPI setup and we just found out that the diaphram had ruptured on the regulator and he was getting way too much gas at idle.  It was still getting up and going when you stood on it, but it idled like .
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Re: '88 5.0 starting/running problems

Reply #51 –
But when you stood on it, was it a sharp spike of the pedal or slow smooth rev-up?

If I stab the pedal this one will bog hard.. but if I push it in smooth it'll rev to 5k+. (when warm.. if cold, it just bogs a lot no matter what you do)

I did say I didn't see any gas in the vacuum line to the FPR.. but it could be that I just missed it. I don't know.

Re: '88 5.0 starting/running problems

Reply #52 –
Aight, so what do I check next? Sorry if I sound a bit impatient.. (I'm a little anxious, if anything) but I was hoping that turning a few wrenches on the '88 would help take my mind off this  LSC.

Is it possible that I've put in too many additives to the gas? If this is to be believed:

http://www.lincolnsonline.com/article99.html

..then I went overboard. 2 bottles of STP Gas Treatment, plus that bottle of fuel stabilizer.

I can se together a few more bucks for a FPR if that were indeed the culprit.. but I can't afford to keep throwing parts at it wildly, hoping it will eventually work right.

Re: '88 5.0 starting/running problems

Reply #53 –
Oddly enough, now that I have this LSC parked out front, I need this Bird running somewhat urgently. Since this is not my house, I am now starting to get the "yard as a parking lot" , and all cars need to be functional. I can justify having two Birds and an LSC because between those and the ZX2, everyone in the house would have a car available to them if needed.. but only if they're all running.

Initially when I got the LSC I was told I needed to have the '88 gone in 2 weeks.. but I have since made my line of reasoning clear, and the '88 has now been tentatively labelled "my fiance's car". Well, da woman need a runnin' car. :D

Re: '88 5.0 starting/running problems

Reply #54 –
When it's cold, I have to really work the pedal and rev it a lot to keep it going.. but once it's warm, I don't. Also, when it's cold, any time I step on the gas at all, it bogs.

This was exactly the same problem I had with my 3.8, and a new IAC straightened it right up. You may have already taken care of this issue, but thought I'd make you feel a bit more confident about it if you have (had) any doubts.

Re: '88 5.0 starting/running problems

Reply #55 –
Well, the IAC is under suspicion, still.. by me, at least.

Re: '88 5.0 starting/running problems

Reply #56 –
I am new with these cars all together, and am learning a lot from the guys / gals here, and certainly don't want to send anyone in the wrong direction, but the difference was night and day when I changed the IAC. Another side note, the only code I was getting was for the EGR valve / sensor, but a new EGR valve and sensor did not take care of the problem. I don't have any clue how to test the voltage for any of these, so I was kicking around in the dark and throwing money at it.

I changed EGR valve and sensor, wires, plugs, cap, rotor, and noticed a slight difference with each item, but IAC was the key to it all.

Re: '88 5.0 starting/running problems

Reply #57 –
Bird351: Maybe you've already addressed this but I'm too lazy to read all of your posts. :sorry:
 
This 88, was is sitting for a loooong time before you bought it? Might your problems be something simple like an extremely clogged fuel filter or, God forbid, a clogged sock on the fuel pump? Both are relatively cheap fixes but the second would mean dropping the tank.
 
Also have you checked the dizzy cap? Sometimes they will look fine but they will pit under the contacts for the rotor button causing really poor spark.

Re: '88 5.0 starting/running problems

Reply #58 –
Quote
I can se together a few more bucks for a FPR if that were indeed the culprit
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?
Death awaits you all with nasty, big, pointy teeth.

1988 5.0 Bird, mostly stock, partly not, now gone to T-Bird heaven.
1990 Volvo 740GL. 114 tire-shredding horsies, baby!

Re: '88 5.0 starting/running problems

Reply #59 –
Quote from: thundergrowl
Bird351: Maybe you've already addressed this but I'm too lazy to read all of your posts. :sorry:
 
This 88, was is sitting for a loooong time before you bought it? Might your problems be something simple like an extremely clogged fuel filter or, God forbid, a clogged sock on the fuel pump? Both are relatively cheap fixes but the second would mean dropping the tank.
 
Also have you checked the dizzy cap? Sometimes they will look fine but they will pit under the contacts for the rotor button causing really poor spark.


It did sit.. but I replaced the fuel filter in October when I was trying to get the car back here. Don't know about the sock on the fuel pump.. but from what I've been told, it would be difficult to rev the engine if the sock were clogged up. I am able to get the engine to rev over 5k, I just have to be slow with the pedal on getting there.

I replaced the cap and rotor a couple days ago, along with putting on a new coil and re-gapping all the plugs.