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Hesitating?

As you may know I just recently purchased a 1988 cougar xr-7. The car has been stored in a garage on and off for the past 10-15 years. This car is my daily driver and I've noticed something about it. When I drive it, it seems to hesitate when I push on the gas so in order to make her go I push on the gas harder which is taking its toll on my gas tank!  Also when I first start her up she revs up real nice but then almost stalls but revs up then almost stalls again for a couple tries then she either stalls completely or is fine.  When you can here this you can also see it happen on my rpm speedometer it goes up to two then back down to a half then up and down. My dad told me that the fuel something needed to be cleaned so we bought some seafoam and put it straight in the gas tank. It was fine for a day or so and now its starting to hesitate again. I had my boyfriends step dad who is a mechanic take a look. He listened and decided my car may be fuel hungry. He also said that since my car has been stored on and off for the past 10 years that contaminents may be at the bottom of my gas tank and now that im putting gas in it is mixing it up. Today I bought a new fuel filter for my car and he is installing it tonight.  Does anyone else have this problem or does anyone have any other suggestions? Your comments are appreciated!


Hesitating?

Reply #1 –
They may be on the right track...but in my experience with these cars, it's probably something electrical. Does your dad (or anyone else) have a code scanner, per chance? That's about the best way to figure out what's going on with all of your sensors.

If I were a betting man, I'd say the throttle position sensor (TPS) is shot. Could also be related to the EGR, EVP, O2 sensors, cannister purge solenoid, maybe even the MAP sensor. But without the codes being read it's a  shoot. You could be throwing good money after bad for a looooooong time unless you know for sure what the computer is telling you.

Hesitating?

Reply #2 –
I tend to agree with Eric, but if I were also a betting man, I may seriously consider the TFI-IV ignition module.  The pattern, you Samantha, described with regard to your tach reminds me of one of the first problems I had with my 88 XR7.
Where I am going with this is, a learning curve for me, was learning how to talk to the computer.  When I finally figured out that I needed a code reader (lol, long before I found out about jcassity's DIY), the error code pointed me in the direction of the TFI.

The point is, Eric's right when he says:
Quote from: EricCoolCats;240984
But without the codes being read it's a  shoot. You could be throwing good money after bad for a looooooong time unless you know for sure what the computer is telling you.

So before you go for the mechanics of the problem, be sure to consult the electronics.  LOL.
Let us know how it turns out! :)
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Operation: X Marks the Spot
5.0L SEFI, AOD, 8.8" 3.02 TracLok - All Stock

Hesitating?

Reply #4 –
I experienceds a similar symptom.  It could be the gas or gas station.  Try switching brands of gasoline, e.g. if you normally run Exxon, try BP.  My suggestion would be a couple of tanks of Shell or Phillips if either is available in your area. 

Also, think about replacing the fuel filter.  It's probably due, regardless of what else might be wrong.

Those are other options, but my first move would be to check codes as mentioned previously.
__________________
Twin '85 TCs
White/ Grey 2-tone
#1 (left): undergoing top-to-bottom rebuild     
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Hesitating?

Reply #5 –
X2    could also be a fuel pump issue  if you have access to someone with a gauge I would check it under load


Quote from: EricCoolCats;240984
They may be on the right track...but in my experience with these cars, it's probably something electrical. Does your dad (or anyone else) have a code scanner, per chance? That's about the best way to figure out what's going on with all of your sensors.

If I were a betting man, I'd say the throttle position sensor (TPS) is shot. Could also be related to the EGR, EVP, O2 sensors, cannister purge solenoid, maybe even the MAP sensor. But without the codes being read it's a  shoot. You could be throwing good money after bad for a looooooong time unless you know for sure what the computer is telling you.

Hesitating?

Reply #6 –
I replaced the fuel filter today which was really dirty! Let the car sit for a while then started her up and its still hesitating. So tomorrow I'm going to call Firehawk (my dad knows the one guy) and see how much its gunna cost to get the car scanned. And once I find out what's wrong ill have his step dad fix it instead of having to pay a whole bunch of money!


Hesitating?

Reply #7 –
IAC valve is my first thought. As Eric mentioned, you may have a "dead spot" on your TPS.

You may consider running Seafoam into the vacuum system on the engine rather than pouring it into the fuel tank. This helps to "blow out the cobwebs."
Refer to the instructions on the can for more information.
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Hesitating?

Reply #8 –
I didn't read anywhere if the engine light came on. If its throwing a code should light it, but maybe not.
Old Grey Cat to this.88 Cat, 5.0 HO, CW mounts, mass air, CI custom cam, afr165's, Tmoss worked cobra intake, BBK shorty's,off road h pipe, magnaflow ex. T-5,spec stage 2 clutch, 8.8 373 TC trac loc, che ajustables with bullits on the rear. 11" brakes up front. +

Hesitating?

Reply #9 –
nope no engine light. only when it stalls out.


Hesitating?

Reply #10 –
Buy a can of the Seafoam in the spray can and spray out the sensors on the TB. My car did the same thing when I go it and started to do it again about a month ago. Sprayed them out a few time and Im back to wasting gas cause i want to not cause I have to.
1986 Cougar LS

Hesitating?

Reply #11 –
Quote from: DVP;241081
Im back to wasting gas cause i want to not cause I have to.



Haha I love wasting gas ! But I filled her up less than a week ago like over filled her and now I'm almost out of gas and I basically just drive to work which isnt too far and home and to my boyfriends its just annoying.

On tuesday my dads mechanic is going to scan my codes and hopefully it will tell him what the problem is!

I'll update everyone if I find out the problem.


Hesitating?

Reply #12 –
I have had the same problem in mine as well. I have been considering a tune up and have yet to have it done. Last time I drove it, it realy got on my nerves as well. If I have it tuned up, I'll let you know if that helps any.

Hesitating?

Reply #13 –
Clean the iac motor,replace the plugs and wires,remove and decarbon the egr,set the tps and all should be fine.
Your surge at idle is more than likely related to the iac being dirty but could be the tps,not likley though.
Not a fuel pump,fuel or tank issue at all.
If it where a lack of fuel from the pump it would be losing power when accelerating not surging at idle(i've had a few pumps go on me and none surged at idle(they ran the best at idle as little fuel was required).
The fuel pump has a sock on it that will prevent  from going into the fuel system, there would have to be a swamp in your tank for it to be plugged and again you would have no power when you step on the loud pedal.
As for the tfi module,that will not cause a surge or lack of power it will cause an intermitten instant dye-out condition with a hard long crank restart or no start at all so it's not that.
Don't bother taking it to a mechanic just do the tune up,it needs it anyways.

Hesitating?

Reply #14 –
you only need a paper clip to pull codes.
I too am worried about old gas and "shelack" on the interior of the fuel lines or even the injectors.  You need to find out from the prevous owner precisely how often the car was ran. 
There are tiny little tear drop filter screens in the top of each injector which can be replaces.  I suggest you do this cause i would.  The reason i would do it now is because someone decided seafoam was a good idea.  the seafoam might have loosened things up and everything that broke away is caught on the tops of the injectors.  Good call on the seafoam as it turns a bad thing into an opportunity.

FIRST

MAKE SURE THE ENGINE IS HOT BEFORE PULLING CODES.
1-with key off , install paper clip
2-turn key forward or start your car.  Either way codes will begin now.
-----a series of quick flashes will occure which are impossible to catch followed by a pause. then codes start dumping out.  This is your computer looking out into the components and logging in information as wel as counting the cylinders.  These are called Fast Codes,,,,,,,ignore this part.

-----there are two groups of codes ,, codes your car has now and ocdes that are in memeory.  when the "now" codes are done dumping out, there will be a long pause.  suddenly your memory codes will start to be displayed.
-----have paper and pen in hand
3-watch codes displayed by check engine light , count them and jot down the numbers.

a second part to code pulling is to include a 1.00 radio shack 12v buzzer so you can hear the codes.

using just a paperclip will activate your check engine light and will strobe the codes.  Using a buzzer to hear allows you to listen while you write and you dont have to take your eyes off the paper while you are looking at a flashing check engine light, glancing down wondering if you missed a strobe or not.


SECOND
MEASURE TPS VOLTAGE
-with key on only, prob the tps green wire with a stick pin.
-Measure your green wire TPS voltage to ground and insure is is about .6 to .9 volts dc.
-if voltage is high, it ususally leads to a high idle situation.  the mounting holes of the tps can be filed with a round chainsaw file so the holes are "egged" or oval.  remount the tps and barely snug the screws.  remeasure your tps voltage, rotate tps slightly to dial in your .6 to .9vdc reading by means of your new modified tps work.
-using a cheap buttstuffog meter (with a needle), sloooooowly open the trottle linkage while watching the voltage increase.  if there is a momentary miss or jump in the meter needle, there is an open spot in the tps and it needs replaced.


THIRD
CHECK 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.
-hook 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 occures.

FOURTH
Get a couple cans of carb cleaner/brake cleaner.
Clean out the IAC and the EGR ports.

FIFTH
Remove the Air Charge Temp Sensor and clean off the little "dingle berry" on the end of the sensor.
It should read abotu 50kohms per my diy link bone cold.  As the temp increases, the resistance decreases.
So... you can hook your meter up to the pins on the sensor and set your meter to the proper range.  Ovserve it is about 50kohms.  Now use a lighter to heat up the little dingle berry by sweeping the flame near the element.  the resistance should start to drop and as it cools down, it will increase.

Sixth
Waste a whole can of wd-40 on various vacuum sensors.  Unhook hoses or solenoids and spray wd down in them.  THis would include the vac hose that goes down to your cruise control (large hose going into the driver fender well up near the fire wall.  Lubricating the vac sys will help the plastic / rubber parts in the various sensors move more free.  Also spray into the EGR VAC fitting. 

SEVENTH
Wait unitl night time.  Check to make sure any easy to get to spark plug is getting nice bluish/white spark. If not, replace the TFI or the hull effect/stater assmebly.

enough for now i suppose.:D