Driving shouldn't be so stressful

Phil04

Registered User
Alright, I have been trying to diagnose what is up with my sc and keep coming up with more questions than answers. My biggest problem right now is rough idle, it seems like it just can't choose what rpm to be at. My car has been running very rich, which may also lead to rough idle. My Oil pressure gauges often pegs at low, causing my check gauge light to come on. It will sit there and rise into low normal, then fall to low, then rise, ... Starting from a stop I get really bad chatter after driving around for a while. When acclerating moderately to wot, I get little hesitations as I accelerate. Very hard to shift into 1st after driving around a while which from reading posts I am thinking is due to the pilot bearing. Also becomes hard to shift into second. I have hooked a modis up to the vehicle to run codes, had bad tps and map sensor. Replaced them, still running rich. No signs of O2 sensors being bad, but I guess it is possible. The plugs are new. Also, my car is having problems starting. Takes way too long and sometimes I have to try twice. I had the battery tested, and it tested fine. However, the guy told me my starter was only drawing like 10V. I am wondering if that is due to a bad starter or a bad ignition system all around. However, no codes came up when I ran the modis. My lights dim every once in a while at a stop, including dash and cd player lights. There is definitely something wrong with my electrical system, just can't seem to narrow it down. Any input would be greatly appreciated.
 
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Phil04 said:
Alright, I have been trying to diagnose what is up with my sc and keep coming up with more questions than answers. My biggest problem right now is rough idle, it seems like it just can't choose what rpm to be at. My car has been running very rich, which may also lead to rough idle. Starting from a stop I get really bad chatter after driving around for a while. When acclerating moderately to wot, I get little hesitations as I accelerate. Very hard to shift into 1st after driving around a while which from reading posts I am thinking is due to the pilot bearing. Also becomes hard to shift into second. I have hooked a modis up to the vehicle to run codes, had bad tps and map sensor. Replaced them, still running rich. No signs of O2 sensors being bad, but I guess it is possible. The plugs are new. Also, my car is having problems starting. Takes way too long and sometimes I have to try twice. I had the battery tested, and it tested fine. However, the guy told me my starter was only drawing like 10V. I am wondering if that is due to a bad starter or a bad ignition system all around. However, no codes came up when I ran the modis. My lights dim every once in a while at a stop, including dash and cd player lights. There is definitely something wrong with my electrical system, just can't seem to narrow it down. Any input would be greatly appreciated.


Well, I'm new at this, but this is what I've done... tighten your IC tubes... Get some of Wynn's (tbird88) Gasket if you don't want to use RTV -- that leak could cause your choppy idle .. I have the same problem with mine starting.. idk what it is though.. if you find out, let me know :D And what kind of plugs did you use? I think double plats are the best.. but I'm not 100% sure.. and you've got a parasitic draw -- that would cause the dimming.. I had that problem, but it was my alternator... well, good luck.

-Chad
 
thanks for the reply. It amazes me that there are so many posts on these problems yet no definite answers have been reached. I will be getting those IC gaskets shortly, along with my custom double IC. As far as the spark plugs, I will be replacing whatever is in there shortly with autolite double plats. I have read it is possible to have spark plug wires running to the wrong location, so I need to check on that. Something is definitely up with my fuel injection. Driving lightly, nice relatively slow accelerations, I get excellent gas mileadge. Start getting a little heavier foot, there is a dramatic difference. I understand there will and should be a difference, but 22mpg vs 11mpg is pretty significant. I know my engine is running rich, just not why. New TPS and MAP, haven't checked MAFS yet. Ran codes w the modis and saw no problems w O2 sensors, they read rich. I currently have no upgrades, everything is stock but the differential, which doesn't affect anything. I went through the car was the other day, and withought thinking turned my car off when i drove in, not like it really matters. Well, after it was done...car would not start. I had nothing!. I had to push my car out of the car wash and get it jump started. So I got the battery checked out, checked out fine. I don't think the alternator is bad, but anything is possible. No water had gotten on anything, so there was no reason for the car not to start. And for the car to just be absolutely dead...after driving around for a while... makes no sense!
Oh, also forgot to mention all my shifting woes. Hard to get into first, unless i put it into first initially, grinds into reverse, takes like 2 seconds to shift into second often. From what I have read it could be the Pilot bearing causing this. Also the brake master cylinder could be at fault. I have read the cam sensor could attribute to the rough idle. Since my starter is apparently only drawing 10v it is apparently bad, unless there is a bigger problem behind it. My AC will not get cold. I am not sure what can and can't cause this.
 
Phil04 said:
thanks for the reply. It amazes me that there are so many posts on these problems yet no definite answers have been reached. I will be getting those IC gaskets shortly, along with my custom double IC. As far as the spark plugs, I will be replacing whatever is in there shortly with autolite double plats. I have read it is possible to have spark plug wires running to the wrong location, so I need to check on that. Something is definitely up with my fuel injection. Driving lightly, nice relatively slow accelerations, I get excellent gas mileadge. Start getting a little heavier foot, there is a dramatic difference. I understand there will and should be a difference, but 22mpg vs 11mpg is pretty significant. I know my engine is running rich, just not why. New TPS and MAP, haven't checked MAFS yet. Ran codes w the modis and saw no problems w O2 sensors, they read rich. I currently have no upgrades, everything is stock but the differential, which doesn't affect anything. I went through the car was the other day, and withought thinking turned my car off when i drove in, not like it really matters. Well, after it was done...car would not start. I had nothing!. I had to push my car out of the car wash and get it jump started. So I got the battery checked out, checked out fine. I don't think the alternator is bad, but anything is possible. No water had gotten on anything, so there was no reason for the car not to start. And for the car to just be absolutely dead...after driving around for a while... makes no sense!
Oh, also forgot to mention all my shifting woes. Hard to get into first, unless i put it into first initially, grinds into reverse, takes like 2 seconds to shift into second often. From what I have read it could be the Pilot bearing causing this. Also the brake master cylinder could be at fault. I have read the cam sensor could attribute to the rough idle. Since my starter is apparently only drawing 10v it is apparently bad, unless there is a bigger problem behind it. My AC will not get cold. I am not sure what can and can't cause this.


90% of A/C problems that I've read about are due to the compressor (it's about 100$ from ford with a mechanic discount) -- and plugs in the wrong places.. I'm guesing you mean in the wrong firing order -- I'm sure there is a diagram around here.. I'll look in a little bit, I've got to pick up my sc from the shop :D and there are plenty of definate answers... they just need to be compiled into one guide :) The FAQ has alot of stuff, but I don't think it would help your situation any... Good luck.

-Chad
 
Your starter only getting 10V sounds like a bad battery cable. I had one that was bad way up into the insulation so the cable looked brand new, but it was bad. That bad cable caused the same starting problems you've described.
I once had to get the car towed home because it would not start on a parking lot and I tried for 1 hour to start it before calling rollback. Once the rollback left the car fired right up, I wanted to set it on fire right there. :mad:
Sounds like you have multiple problems. I'de start with the battery cables as they may be the root of some if not all of your problems.
 
MIKE 38sc said:
Sounds like you have multiple problems. I'de start with the battery cables as they may be the root of some if not all of your problems.
Agree. I'd clean the clamps and posts regardless of how they look, then proceed to the connections at the relay and the starter, then check the charging voltage at idle, and then test the battery electrolyte density with a floating tester. Then check the engine mounts. ;) None of this should take much time. Then get back with us. :cool:
 
Thanks guys, I will try some of those things out. I have a feeling my MAFS is acting up, as that is just about the only thing I haven't replaced. I will probably replace that, the IAC, and the ECT sensors. I ran codes again today, nothing. So it must not be that serious. Could even be a clogged up cat or something. Either way, its nothing detramental.
 
I am def checking the battery wires asap. The first thing I did was have the battery checked. A bad connection could explain a lot of my problems. I understand the basics of circuits, took a class while studying engineering. I just am not familiar with what everything does and how it all interacts. Could a bad connection to the batter cause a lower voltage to all the sensors and such? Occasionally, when I come to a stop, my lights may dim and then brighten. The gauge lights also dim at the same time. There has to be some simple connection for all these problems. Could a bad connection also lead to insufficient spark from the spark plugs? I haven't gotten too much into electrical stuff yet. So far I have done drivetrain and am in chassis at wyotech. EMS is next lol. I am just wondering if the electrical system isn't being properly supplied, could all the sensors be putting out less voltage than they should be, making the computer think things are different than they actually are.
 
You may have a headlight switch going bad...mine did...add freon to your A/C they can leak down...mine did...as for your oil pressure the sending units on these go bad all the time......mine did ....it's nothing more than a glorified idiot light anyway... it's on the front of the engine block drivers side of the water pump,very cheap very easy fix but check the wire connection there first it may be that simple. your hesitation at accelleration may be clogged cats or bad plugs and wires or fuel filter etc. , but the knocking you were referring to had me wondering if you were using a high enough octane gas...these cars don't like cheap gas at WOT. Use 92 or 93 octane if you don't already.... early detonation is BAAAADD ;) ..that could also account for the appearance of running rich....Just my .02

Rick
 
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Phil04 said:
I am def checking the battery wires asap. The first thing I did was have the battery checked. A bad connection could explain a lot of my problems. I understand the basics of circuits, took a class while studying engineering. I just am not familiar with what everything does and how it all interacts. Could a bad connection to the batter cause a lower voltage to all the sensors and such? Occasionally, when I come to a stop, my lights may dim and then brighten. The gauge lights also dim at the same time. There has to be some simple connection for all these problems. Could a bad connection also lead to insufficient spark from the spark plugs? I haven't gotten too much into electrical stuff yet. So far I have done drivetrain and am in chassis at wyotech. EMS is next lol. I am just wondering if the electrical system isn't being properly supplied, could all the sensors be putting out less voltage than they should be, making the computer think things are different than they actually are.

Yes bad or eratic battery cable connections can cause this and if you're not getting full power through those connections of course nothing else in the system is as well. Computers and sensors cannot properly do there job if there not getting the required power.
Dimming lights is clear proof either your connections are intermitent(loose, bad or dirty) or you have something shorting. Check all your ground connections as well as they are part of the circuit and will cause the exact same symptoms.
 
I appreciate all the good feedback. First I want to clear up there was never any knock. Nothing that serious. Yeah, I am not too concerned about the fuel pressure gauge, but there is another sensor that goes to the eec that could prob cause some probs if it is malfunctioning. A lot of things have gotten better since I finally remembered I hadn't cleared the codes. I am going to go at the battery tomorrow and see what I can do. How do I check to see if I have enough freon?
 
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