Hesitating? Reply #15 – November 02, 2008, 11:45:12 AM QuoteCHECK your fuel presure with car running. Should be about 35 or so psi, quickly disconnect the vac line on the fpr and cover the end with your finger- presure should jump to about 40 or so psi.With a stock cam those 2 numbers will be further apart. If they were that close together I would start looking for a rather large vacuum leak.Vac. line disconnected ~40 PSI (35-45 PSI is within spec according to Ford)With the line connected -- generally 10-12 PSI less with the stock cam and @ idle RPM....Quotehook your fuel pres tester up and tape the guage to your windshield. reconnect your vac line to the FPR. While driving, observe the presure while your transmission cycles through the gears. Any drop into the 20's will warrent a fuel pump in my opinion. This is a true load test of your engine while the problem occuresAnything below what you got @ idle with the line connected will be a problem......At WOT you should see the same value as with the line disconnected at idle or VERY CLOSE to it. Within 2 PSI.QuoteWaste a whole can of wd-40 on various vacuum sensorsOr you can buy a vacuum guage and not make a mess. A nice tutorial on vacuum diagnostics here: http://sbftech.com/index.php/topic,3020.0.html Quote Selected
Hesitating? Reply #16 – November 02, 2008, 02:47:25 PM I noticed you used some seafoam good stuff but have you tried using it to clean you the VAC system. Pull a vac line and spray it in the line and let is sit for a few min. Then start it up and it will smoke but that is all the nasties being burn up. Then you could also look over http://www.fordfuelinjection.com/ on how to test those sensors. They give and excellent break down on each sensor and how to test it. Quote Selected
Hesitating? Reply #17 – November 03, 2008, 12:57:39 AM not sure what the purpose of the quotes were but ignore what i said.i said with your vac line disconn =40 or so psi> the correction was "~40 PSI (35-45 PSI "I said with your vac line connected=35 or so psi> the correction was "10-12 PSI less than disconnected"I said with the guage taped to the windshield driving=Any drop into the 20's is bad. Meaning 40-45psi minus 10-15 psi.> the correction was trival but it basically said the same thing i did. Not many people have actually done the pres guage to the windshield test. The needle will cycle up and down in relation to the load. At wide open throttle, as the rpms are high, the pres will naturally be a little low. As the speed and transmission gains in the gear you are in, the presure will come back up to as specified with the correction > "within 2psi" of what presure you had with the line disconnected. If you read the correction,, a bad reading would be in the 20's on presure. Reading fuel presure while under a load is not linear on the guage. It is not a simple number and thats why anything in the 20's will reduce power cause the fuel flow is low compared to the demand or engine consumption at higher rpms.I said to waste a can of wd40 to lubricate the internal moving parts of the vac piece parts. (due to sitting so long)> the correction was to not make a mess. Buy a vac guage instead. Im not really sure how just the simple purchase of a vac guage will lubricate the internals of the vac system. Using the vac guage still will not add any lubricant.Im not sure what all was achieved by the quotes and then say the same thing i did sending the message that i passed out bad information. Im just confussed on what was wrong wth the structure of the message keeping it fairly simple and to the point. Quote Selected
Hesitating? Reply #18 – November 03, 2008, 02:55:33 AM For the fuel pressure it was an elaboration on what you said, expanding on it and correcting the #'s you stated. FWIW a pressure drop in the 20's is bad, but if idle pressure without vacuum is 45 and observed pressure under load @ WOT is 35 there is an issue as well....Someone could misconstrue what you said/typed. Your expansion on it in the post above was much better.The Vacuum/WD-40.....Why make mess if you don't have to? Better to check to see if the person has a vacuum problem and to show them how to check for it and diagnose the situation IMHO. If a vacuum hose needs to "lubricated", it most likely needs replacement FWIW. Anybody who owns one of these cars with the desire to keep it and do a good amount of the repairs/maintenance themselves SHOULD have a vacuum guage as well as some other essential tools (something to read codes with, for example).QuoteIm not really sure how just the simple purchase of a vac guage will lubricate the internals of the vac system.In the 11 years I've owned my car I've never had to "waste a whole can" of WD....In fact, I've run a cleaner/solvent through the vacuum tree only ONCE. [SIZE="5"]Nobody's perfect and it wasn't an attack on you. I honestly don't see why you are defensive over it...[/SIZE] Quote Selected
Hesitating? Reply #19 – November 03, 2008, 10:34:17 PM ok,, gotcha,, now i understand, you were just fine tuning the details. Quote Selected
Hesitating? Reply #20 – November 04, 2008, 11:24:48 AM Ok I went to the mechanic today and of course my car hesitated the whole way there but it did NOT hesistate when they drove it. He didn't find anything really wrong with it. But he DID clean the idle air control motor and the throttle body which was VERY dirty. Now i'm going to wait and see if it does it again :( Quote Selected
Hesitating? Reply #21 – November 04, 2008, 02:54:48 PM with no check engine light coming on,, id bet money its fuel delivery related.Id also bet money its the fuel injector screens. Quote Selected
Hesitating? Reply #22 – November 04, 2008, 04:07:54 PM If its just a hesitation then clears up, sounds more like a vac problem, where i don't know.Since no light and no codes.Or DAD did something to stop her from goin fast. Quote Selected
Hesitating? Reply #23 – November 04, 2008, 10:00:50 PM what motor dose it have no one has asked that yet that i can see. Quote Selected
Hesitating? Reply #25 – November 04, 2008, 10:47:13 PM yeah its a 5.0. and no dad didnt do anything that car goes fast when you step on it believe me! Quote Selected
Hesitating? Reply #26 – November 04, 2008, 10:52:12 PM my car did it when i got it but i dont rember what i did to stop it lol and i dont know shiznit about the xr7s lol well cougars at all too Quote Selected
Hesitating? Reply #27 – November 04, 2008, 11:02:26 PM well im jus hoping it isnt anything to major! Quote Selected
Hesitating? Reply #28 – November 04, 2008, 11:03:44 PM ya they are bad on gas even if u put around. my car did the same thing when my dad gave it to me after it sat for 5 years stright. try puting some fuel cleaner in it use lucas one 100% actoen but with the actoen only use 3oz for 10gal. do not go over 3oz tho. Quote Selected
Hesitating? Reply #29 – November 05, 2008, 07:33:13 PM So I was driving today and it hasnt hesitated at all thanks for all the help guys! Quote Selected
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