Heres the story about a decrease in power...

[Dbeck002]

Ok just recently my car has been running warmer than usual, not hot, but just warmer than it always has.

The idiot temp gage showed the needle (with the fan on) to always be below the second line or the L on the normal. now it almost passes the A which is weird, it never did this.

Along with the tempurature increase there is a huge power loss of low end. the car isnt accelerating like it used to before this.

car has a lot of bolt ons but stock heads.

fuel pressure is normal and so is timing, i checked both of these. i hear the fuel pump so thats working. i dont understand what the hell is going on though, my car just seems so... slow....

 

[grrrrrrr]

Double check your timing. I read in Haynes that timing can adversely affect the cooling abilities of the car. Obviously it has an effect on hp as well. Check to make sure your timing is still spot on and also check out the dizzy as well and the rotor. If the rotor is loose or vibrating around causing your timing to fluctuate you could have these problems... I know I did...

 

[Dbeck002]

thanks for the reply dude. i checked timing 50 times and its at 16 degrees just where it has always been and was running fine. just all of a sudden now it chooses to loose power and run warmer. i dont know what the hell is going on!!

 

[HISSIN50]

please provide year and mods (just the important stuff) - esp. about the cooling system, like what elec fan you have, how it is controlled, what your stat rating is, etc etc.

are you getting any codes? when the car really does get hot (~226, IIRC), it will cut timing back. i might check the ECT to ensure it is not out of calibration (unless you know that you are really running hot vs having a bad-gauge day).


But more info is really needed. and if you have any buds with a spare temp gauge, i would hook it up temporarily to see how it does. good luck,

 

[Dbeck002]

To answer your questions hissin.

the electrical fan is a volvo S40 fan that used to keep my engine dangerously cool. it is controlled by a switch under the dash which activates the relay. this system has been working well for almost half a year, i think that its actually keeping my engine from getting dangerously hot and i can thank the fan for this.

the mods are at the bottom of my website below.

the actual temp of the car i do not know but when i put my hand on the manifold its about 30 degrees hotter than it usually was. the manifold was so cool at times you wouldnt know the engine was just ran.

year is 1991 LX and stat is a Mr Gasket 180 performance thermostat that as i mentioned earlier, kept my engine overly cool with the fan running.

 

[TheUser]

sounds like maybe this might be for the best. If you're not overheating, it's probably fine. You probably don't want your motor really cool. Some of the sensors only work after a given temp (O2 sensors don't work until around ~160, I believe). My intakes are always hot after I drive my cars, so I'd say warm is normal. I'm not sure how you've trained to feel a difference in temperature, but the "30* feeling" might be a little inaccurate.

Above all, as with anything, guages might lose accuracy after a period of time, so the accuracy of the guage is in question as well.

If your coolant isn't boiling, I wouldn't worry too much about it

 

[Dbeck002]

Ok about the rotor, its not wobbling and is solid. i still dont understand what the hell is going.

i am kinda irritated by this because this car is my baby and always ran 100%. i just bought 24 lb injectors and 190LPH fuel pump, i will install these in a couple days and then dyno tune it. I want her to run good already...

 

[Dbeck002]

TheUser i know im not a mind reader or gypsy but i can definately tell the difference in temp of the upper manifold. its very profound, i know this car like the back of my hand, in and out. the temp difference is read accurately on the retard stock gage as funny as it sounds. its not the actual temp that bothers me, its fine but it is higher than it used to be which means something is different. it could be running a little bit lean because of the injectors being crummy as they are old, so i bought injectors and a holley 190. if anyone else has any tricks up their sleeve please reply, this is bothering me.

thanks for those who have replied so far

 

[jerry beach]

You should find out how hot its running first off. Get a cheap guage or borrow a laser thermometer. Your engine coolant should be around 180* because the stat will keep it from running any cooler. If you cooling system is in good shape that is the temp it will run at if you leave the fan on.

Pull the trouble codes, you may have an O2 sensor gone bad or something. Dirt on the MAF wires that are in the intake tract. Make sure you put the spout back in after you checked timing too. I have done dumber things. Check the air box where the filter is. Take the filter out and look, you may have sucked up a bag or something stupid like that. That would cause what you describe.

 

[D347643]

i "heard" if your engine gets to hot the comp will start to pull timing while you're driving....is this true?

 

[jerry beach]

Yep, its true. Hissin said that above. You find a bag in the air box? Buddy of mine got a bag wrapped around the DS and it ate the seal out of his rear end.

 

[Dbeck002]

You should find out how hot its running first off. Get a cheap guage or borrow a laser thermometer. Your engine coolant should be around 180* because the stat will keep it from running any cooler. If you cooling system is in good shape that is the temp it will run at if you leave the fan on.

Pull the trouble codes, you may have an O2 sensor gone bad or something. Dirt on the MAF wires that are in the intake tract. Make sure you put the spout back in after you checked timing too. I have done dumber things. Check the air box where the filter is. Take the filter out and look, you may have sucked up a bag or something stupid like that. That would cause what you describe.

jerry thank you for the awesome suggestions but i have done them all.

no bag sucked up under the fender.
checked maf, was spotless since i recently cleaned it.
O2s were replaced 8 months ago with bosch's.

the engine itself is not running hot, its just warmer than before which is what worries me. so i am positive the computer is not retarding the timing.

there is one thing that i did notice today, i pulled the plugs and they have white residue on them. am i running lean? if so, i will bump fuel pressure up to 45 if i have to just to keep the engine safe until i get the dyno tune. thanks guys

 

[jerry beach]

Pull the codes. If you have cats, how many miles are on them? They may be starting to clog and that will increase heat and cut power back. Just because something is new, dont assume its good. Running lean will bring temps up. Is it pinging at all? Punch it in 5th gear at 45 mph, and it should sound like BB's in a coffe can. If its going to ping, thats when it will do it. My plugs are always white in the stang. I have no pinging, it just runs right on the edge of lean when you are driving normally. You have to go WOT and shut it down and coast to a stop to read what is happening up there. At least thats what I have been told and it makes sense. I dont mind helping folks that help themselves, so dont mention it. If I help lead you to your problem, then I am doing something constructive instead of just joy riding on the net.

 

[Dbeck002]

Pull the codes. If you have cats, how many miles are on them? They may be starting to clog and that will increase heat and cut power back. Just because something is new, dont assume its good. Running lean will bring temps up. Is it pinging at all? Punch it in 5th gear at 45 mph, and it should sound like BB's in a coffe can. If its going to ping, thats when it will do it. My plugs are always white in the stang. I have no pinging, it just runs right on the edge of lean when you are driving normally. You have to go WOT and shut it down and coast to a stop to read what is happening up there. At least thats what I have been told and it makes sense. I dont mind helping folks that help themselves, so dont mention it. If I help lead you to your problem, then I am doing something constructive instead of just joy riding on the net.

well i like that mentality jerry, thats why im over here on stangnet and not mustangforums (1900 posts there, most were useless).

anyway, the car does not have cats so that is not an issue. i always thought that white on the plugs meant a lean condition.

i didnt understand what you meant by going WOT and shutting oof, maybe im just slow lol

by the way it does not ping under the above conditions. but i do suspect it is running lean and i am going to bump up the fuel pressure as soon as it stops raining!!!

 

[jrichker]

Cylinder balance test:
Warm the car's engine up to normal operating temperature. Use a jumper wire or paper clip to put the computer into test mode. Start the engine and let it go through the normal diagnostic tests, then quickly press the throttle to the floor. The engine RPM should exceed 2500 RPM's for a brief second. The engine RPM's will increase to about 1450-1600 RPM and hold steady. The engine will shut off power to each injector, one at a time. When it has sequenced through all 8 injectors, it will flash 99 for everything OK, or the number of the failing cylinder such as 22 for cylinder #2. Quickly pressing the throttle again up to 2500 RPM’s will cause the test to re-run with smaller qualifying figures. Do it a third time, and if the same cylinder shows up, the cylinder is weak and isn’t putting out power like it should. See the Chilton’s Shop manual for the complete test procedure

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at Walmart.

 

[Dbeck002]

Cylinder balance test:
Warm the car's engine up to normal operating temperature. Use a jumper wire or paper clip to put the computer into test mode. Start the engine and let it go through the normal diagnostic tests, then quickly press the throttle to the floor. The engine RPM should exceed 2500 RPM's for a brief second. The engine RPM's will increase to about 1450-1600 RPM and hold steady. The engine will shut off power to each injector, one at a time. When it has sequenced through all 8 injectors, it will flash 99 for everything OK, or the number of the failing cylinder such as 22 for cylinder #2. Quickly pressing the throttle again up to 2500 RPM’s will cause the test to re-run with smaller qualifying figures. Do it a third time, and if the same cylinder shows up, the cylinder is weak and isn’t putting out power like it should. See the Chilton’s Shop manual for the complete test procedure

Here's the link to dump the computer codes with only a jumper wire or paper clip and the check engine light, or test light or voltmeter. I’ve used it for years, and it works great.

See http://www.troublecodes.net/Ford/
OR
See http://www.dalidesign.com/hbook/eectest.html for more descriptive help
OR
See http://www.mustangworks.com/articles/electronics/eec-iv_codes.html

For those who are intimidated by all the wires & connections, see http://www.actron.com/product_detail.php?pid=16153 for what a typical hand scanner looks like. Normal retail price is about $30 or so at Walmart.

ill give it a try though after i get my 24 lbs injectors in (waiting on my desk)

btw ive done EEC codes all the time but not this one with the throttle, cool.

 

[jerry beach]

Since you dont have pinging, I would not worry about the white plugs. As stated mine always look white. WOT is wide open throttle. In first gear slowly floor it without spinning the tires. Wind it up to 5500 rpm, let off the gas and push the clutch and shut off the engine. Coast to a stop and pull a couple of plugs to look at their color. This needs to be done in an open area where its safe. This will give you an idea of what the fuel mixture is like at WOT. That is where you dont want to go lean. Its normal to run lean at cruise or deceleration.

I have never done this test. If you have no pinging everything should be cool. Its just a way I have been told to check on the tune at WOT. Raising the FP [fuel pressure] will only change things at WOT. The O2's drop out then. Do an amazon search on Charles Probst. He wrote an excellent book on our cars, I refer to it alot. Summit and Jegs also sell his book. Its under $20 and well worth it.

 

[tmoss]

Have you checked to see if your loosing coolant at any rate? That would make it run warmer too and if your loosing collant slowly into the intake, it'd be hard to find.

 

[89roadster]

Are you sure your EGR is operating appropriately and not stuck open some how?

I just wanted to second the motion to check the temp - I had a similar problem where the temp guage was much higher than normal. I replaced the fan with a black magic electric, replaced the water pump, replaced the radiator with an aluminum (really stuff I wanted to do any way) and it turns out that the $5.00 temp sender was bad I was getting crappy performance because my alternator couldn't handle the fan was always on and was also on the way out (I was setting the fan by the guage...d'oh) so the ignition wasn't powered as much as it needed to be.

 

[Dbeck002]

Thank you for the replies people.

1. I do not have EGR on my car, EGR spacer has the holes blocked and pump with everythign EGR related has been removed over a year ago.

2. i know for a fact the engine is running warmer because i can tell by feeling the manifold. its very profound as i said before, not like a hint of warmth, more like its hot to the touch as opposed to warm when it used to run well.

3. my alternator is a brand new 3G that i put in 2 months ago, it can handle the fan.

thanks for the input people, im going to be replacing some fuel delivery components soon i.e fuel pump and injectors (24#). any other suggestions are welcome.