Things that cause hesitation

[Ted B]

OK i have hesitation light throttle only here are the things I know to look for...just for shortness sake ill list off the things i know to look for and if you guys know of anything else or methodology to deduce the root cause please chime in.

1. not enough fuel (all things included from tank to rails)
2. bad injectors
3. bad plugs
4. bad coils
5. car lost its tune...i started a thread on that

Thats about all I can think of off hand.

So far the only thing i have done is while the car is running nice and calm at idle warmed up unplugged each injector one at a time and listed to the engine..for the change then plugged it back in to hear it go back to normal.

If the new plugs don't pan out for me tomorrow I will start numbering and swapping around the coils to see if i get anywhere with that. IF that doesn't work idk...car worked fine before i gave it to the transmission guys, and there work seems solid.

 

[MackDombles]

A faulty egr valve can cause this as well.

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[Ted B]

ok well the hesitation turns out to be a mix of the AIC not being able to seat inside (it ohmed out ok 9ish, vs 10.0 on the new one), and well just shitty spark plugs. so on the up and up she purrrrrs like a kitten but still stalls out sometime for what seems to be load on the engine. Now this could be caused by many a thing...the AC, the fans turning on however now the New IAC seems to pick up the slack and regulate idle rpms like a champ. I mean night and day rev feel its like having the engine balanced. So onto the down and out...the car now falls on its face and the AIC can't seem to keep her running when to much of a load is put on the engine at idle.

However the worst part is now the car feels like a stock mach 1, like i just lost 150 bald wheel eagles on the road somewhere. Car revs out just fine has what feels like stock top end power...feels good down low due to 4.10s, but yeah it's like the blower isn't even on there. I know its there i hear it building boost, and purging like it should, but if the rumors are true and my car has lost its tune WTF over.

Now the big question is, can I somehow check to see if the ECU has the factory ford tune, or an aftermarket tune? My secondary question would be how bad could casual driving short distances be with the car everyday...i commute with it like 3 miles.

 

[MackDombles]

ok well the hesitation turns out to be a mix of the AIC not being able to seat inside (it ohmed out ok 9ish, vs 10.0 on the new one), and well just shitty spark plugs. so on the up and up she purrrrrs like a kitten but still stalls out sometime for what seems to be load on the engine. Now this could be caused by many a thing...the AC, the fans turning on however now the New IAC seems to pick up the slack and regulate idle rpms like a champ. I mean night and day rev feel its like having the engine balanced. So onto the down and out...the car now falls on its face and the AIC can't seem to keep her running when to much of a load is put on the engine at idle.

However the worst part is now the car feels like a stock mach 1, like i just lost 150 bald wheel eagles on the road somewhere. Car revs out just fine has what feels like stock top end power...feels good down low due to 4.10s, but yeah it's like the blower isn't even on there. I know its there i hear it building boost, and purging like it should, but if the rumors are true and my car has lost its tune WTF over.

Now the big question is, can I somehow check to see if the ECU has the factory ford tune, or an aftermarket tune? My secondary question would be how bad could casual driving short distances be with the car everyday...i commute with it like 3 miles.

Pardon if I missed it but I'm assuming this is an Eaton swapped mach1?
If so, check the vacuum line to the boost bypass valve. If they moved it from the top port to the bottom it would cause it to run fairly normal at idle but like stock under a load

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[MackDombles]

Also, do you have a handheld tuner for this car?

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[Eatonualive281]

vaccum leak?

 

[Ted B]

@MackDombles no sir you are mistaken, this is a D1SC procharged mach1, than snapped necks just 3 months ago. short story...necks being snapped "responsibly" i drive my cars not destroy them with shitty shifting...however this poor fella had prob been beat on pretty bad before only 50k miles on it now. fast forward new tranzilla 2011 spec tr3650 with all the upgrades and mcleod cluch and flywheel. got the car back seemed ok, but was hesitating bad and stalling all over the place. fast forward to today, new AIC and pluggs...whammo idles good, however falls on its face sometimes when loaded at idle...and uhmm my bald eagles are missing.

also sorry didn't mention I do not have a tuner..car was purchased from a ford dealer..not a small one either about 9 months ago and ran fine till 2 months ago. Also note with a big frownie face I haven't had the money to buy gauges so idk if things are super wonky, but i know when a car isn't running right where the gauges would plainly show.

 

[Ted B]

@Eatonualive281 nah im pretty sure the vacuum is solid i tore the whole system apart when i replaced a bad idler behind the blower.

 

[Ted B]

@Eatonualive281 well after talking with a few tuners and others who have procharged mach 1's im getting a lot of double check your vacuum lines lol...so here we go again, plus word on the new edge street is the fuel pressure regulator is known to either leak or not work that great.

 

[Ted B]

Well I think i've hit my limit on what i want to do outside in a parking garage with naught the right tools and space to really dig into this problem. Unless I can find some local help Im just going to save up and get the LUND racing tuning kit and have Evolution performance in Aston PA take a look at my car, and just do it right.