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Hi everyone just like the title says really bad mpg for a 4 cylinder turbo id say . Its been doing bad since i got it 3 months ago and been emptying my wallet with 4.29 a gallon at the pump !! Ever since ive done a tune up change spark plugs motorcraft . Cap and rotor motorcraft. Replaced fuel filter. And no luck at all.. I shift smooth under 3000 rpm . I got the boost set up to 14 psi. I don't know what the problem could be any ideas?
 

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could be a host of things. clogged air filter, a problem in the emission system. ignition timing off, bad thermostat, temp sensor.
 

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could be a host of things. clogged air filter, a problem in the emission system. ignition timing off, bad thermostat, temp sensor.
my temp gauge doesnt work and thermostat i should replace when fix the temp gauge right . air filter is a k&n i replaced it . ignition timing could be but i have no clue how to test that.:?: here is a link of what it also does : MUSTANG SVO IDLE PROBLEM BIG ONE - YouTube
 

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Well the engine is running BAD!!! First check to see if the CAT is clogged!!! Do a back pressure test and confirm. Second do a MIN IDLE adjustment along with a TPS adjustment. Check for codes and fuel pressure. But first and foremost check the Fuel Pressure Regulator. Remove the vacuum hose start the car and see if fuel comes out the NIPPLE on the regulator!!! And of course do a fuel pressure test. 39 PSI at idle no vacuum. Also check for defective injectors. You also should check for residual FUEL PRESSURE after shut down. Also Cam timing and ignition timing are critical!! Also clean and check the EGR for proper operation!! Good luck Peace Tom:bigthumbsup:bigthumbsup:bigthumbsup
 

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little info

first pay attn to tom ...hes def in the know
second ur temp gauge and thermostat are 2 different entities
the thermostat is a mechanical device that opens and closes at a specific temp allowing for the coolant in ur engine block to go ur radiator for cooling. ur temp gauge is a sensor that only shows the temp of the coolant in the engine block. now there might be some deviations to that but not many so replacing both at same time might not be necessary..if ur concerned about ur thermostat u can always pull it and test it on ur stove in a measuring cup of water and a cake thermometer. the gasket for the housing might be ok with this. if not they are cheap
 

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To add to what the others have said, ECT could be pooped causing a constant rich stoich.
 

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To add to what the others have said, ECT could be pooped causing a constant rich stoich.

Thanks NAVY i forgot that. GETTING OLD Peace My brother!!! :bigthumbsup:bigthumbsup:bigthumbsup
 

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To add to what the others have said, ECT could be pooped causing a constant rich stoich.
Hey thanks guys i will check all this BUT what is a ECT? What does it do and where is it located?:worship
 

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2It is in the lower intake between cylinder 2&3 . It is the coolant temp sender for the ECM!!! peace tom:bigthumbsup:bigthumbsup:bigthumbsup
 

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2It is in the lower intake between cylinder 2&3 . It is the coolant temp sender for the ECM!!! peace tom:bigthumbsup:bigthumbsup:bigthumbsup
It is located on the top side of the lower intake....just to clarify.

The ECT "talks" to the EEC to provide a feedback of Engine Coolant Temp. This helps the EEC compensate for injector pulse to accomodate rich/lean condition based on engine temperature.
You want a cold start/rich condition when the engine is cold, or first started in the day. When the engine warms up, the stoich will shift to a run/leaner condition. If the sensor is blocked bt crud in the coolant passage, or it is bad altogether, it will throw off the signal to the EEC and stay n a cold start state.
IIRC, it is a 25mm fitting.
 

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Discussion Starter #11
It is located on the top side of the lower intake....just to clarify.

The ECT "talks" to the EEC to provide a feedback of Engine Coolant Temp. This helps the EEC compensate for injector pulse to accomodate rich/lean condition based on engine temperature.
You want a cold start/rich condition when the engine is cold, or first started in the day. When the engine warms up, the stoich will shift to a run/leaner condition. If the sensor is blocked bt crud in the coolant passage, or it is bad altogether, it will throw off the signal to the EEC and stay n a cold start state.
IIRC, it is a 25mm fitting.
ok guys i have replaced ECT it wasnt easy but i got it out and replaced it .now my temp gauge works:bigthumbsup. i also replaced the IAC and set the tps to .92 v. it seeems to run a bit better but it still idles funny at some points i did also check for bad spots on the tps seems to read right from 0.92 to (wot). oh and by the way i have no cat so it cant be a bad cat . How can i test the injectors ? i have no tools to test them or idea how ? and what is the timing on these cars ? My goal for this car is to make around 300-350HP id be happy with that different turbo? .so any ideas guys on how to get there shoot them out here :bounce2:.. anyways back to subject :smilie
 

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ok guys i have replaced ECT it wasnt easy but i got it out and replaced it .now my temp gauge works:bigthumbsup.
then you replaced the wrong sensor.....unless it is wired all messed up.
The gage reads off of the sensor in the block, just below the oil sending unit. (1st pic)
Thee ECT is in the lower intake, nestled btween the #2 and #3 injectors. (2nd pic)
 

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Discussion Starter #13
then you replaced the wrong sensor.....unless it is wired all messed up.
The gage reads off of the sensor in the block, just below the oil sending unit. (1st pic)
Thee ECT is in the lower intake, nestled btween the #2 and #3 injectors. (2nd pic)
hey navySvo the sensor i replaced was the one between cylinder 2 and 3 on top of the block , i see the other one you mean . But unless like you said might be wired weird because my gauge never went up it always stayed down maybe moved an inch or so but never to the middle normal position until i replaced the ECT i gess somehow it helped it ? .. the only time it idles weird is lets say im 40 -45 on the road then i push in the clutch and kill the gas the idle will go down to around 500 rpm then go up 1000 rpm , but since i replaced the ect it hasnt been rough its been low smooth idle ..
 

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Also just incase injectors are bad or just reaplce them , one of my friends friend is selling 42lb lucas injectors for $150 he has a svo too but didnt end up using them . is it good deal? would i be able to put them on ?
 

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Joe check the O2 Ground on the turbo BELL. I move it to a better location and away from the turbo heat. This wire is the return for PIN 49 on the ECM. Normally i just jump it to sig rtn and call it a day. Now some will tell you this is wrong. But it works and i have dun it several times. The Turbo bell is the worst place to install this wire in my experiance Check it very carefully. Peace tom
 

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An idle surge that bad has to be a huge vacuum leak. If you have access to an air compressor make yourself a "boost/vacuum leak checker" out of a 20oz mountain dew bottle top and a tire valve stem. Attach to the inlet of the turbo and have a buddy fill the stem up with 12-18lbs of pressure while you spray all your hoses, intake, turbo compressor housing, intercooler couplers with soapy water... I use simple green in a spray bottle. This will find any leaks small and large quickly. Fix as necessary

Spray around the intake where it bolts to the head.... Ive found alot of leaks around those gaskets that so called experts have missed. Make sure everything is good and sealed. If the idle surge continues, check base timing with spout out, set to 6-10'. If problem still continues look into fuel delivery problems. Reg, badly leaking injectors or pump possibly. If you had an adjustable FPR with gauge we could verify how the fuel pressure bleeds off and determine a fuel issue quickly

Something is telling the ECM to run full rich... even if it where stuck in open loop I doubt fuel mileage would suffer that bad.
 

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Discussion Starter #18
An idle surge that bad has to be a huge vacuum leak. If you have access to an air compressor make yourself a "boost/vacuum leak checker" out of a 20oz mountain dew bottle top and a tire valve stem. Attach to the inlet of the turbo and have a buddy fill the stem up with 12-18lbs of pressure while you spray all your hoses, intake, turbo compressor housing, intercooler couplers with soapy water... I use simple green in a spray bottle. This will find any leaks small and large quickly. Fix as necessary

Spray around the intake where it bolts to the head.... Ive found alot of leaks around those gaskets that so called experts have missed. Make sure everything is good and sealed. If the idle surge continues, check base timing with spout out, set to 6-10'. If problem still continues look into fuel delivery problems. Reg, badly leaking injectors or pump possibly. If you had an adjustable FPR with gauge we could verify how the fuel pressure bleeds off and determine a fuel issue quickly

Something is telling the ECM to run full rich... even if it where stuck in open loop I doubt fuel mileage would suffer that bad.

Hi and thanks for the ideas.. Do u have a write up fo that method of boost leak test woth pics?kinda lost there .. Ive done the cigar test and the only place smoke came was from the throttle body not where gasket is but the middle front .. But there is nothing i can do there . Normal? .. And i will check the timing just waiting on a friend to help kuz i don't know how to check it.. But i have thought of bad injectors but there's no way to check them i know there's tools but expensive .. Ove tried cleaners but no luck... And yes gas mpg is bad feels like driving a 454 haha its bad man . Premium with the switch on.. This weekend ima buy a eec4 code reader to pull codes that should help and il let yall guys know .. Just been waiting for funds . This car emptys my wallet quick lol.
 

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If the smoke test passed i would move on. Pressurizing the system is good but smoke is the best way. You can pressurize the system for leaks on the turbo before the TB but that is not the VACUUM SIDE. So basically if you pressurized the system and find leaks their it wont effect the idle issue. So better look at other options and do some trouble shooting. If you are rich as you are that means you are commanding the ECM to do this. And if as posted above that you have a massive Vacuum leak that should have shown up on a smoke test and you would hear that quite easily. So you totally skipped over the return signal to pin 49 on the ecm and did not even check it. Well your LOSS. Peace Tom:bigthumbsup:bigthumbsup:bigthumbsup
 

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If you had an adjustable FPR with gauge we could verify how the fuel pressure bleeds off and determine a fuel issue quickly

Why cant this be dun with a stock FP regulator????????????? I am lost for words on this one!!!!!!!!:nono::nono::nono:

TONY!!!! How do you accomplish building 18 LBS of pressure in an engine by inserting AIR at lets say the air cleaner or the in side of the TURBO :?::?::?:

Note the pressure testing on turbo piping is dun at the air cleaner to the inlet of the TB. After the TB the only way to pressurize further is to close the intake valves. Then you can pressurize the entire system. This will include the intake upper and lower. Thanks
 
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