'95 Stang overheating

[306DropTop]

:SNSign: Okay folks, after 4 years of following this forum, I'm finally joining and entering my first post. I'm am active duty member in the US Coast Guard , and I've been (patiently) dealing with an overheating issue for the past 4 years that has dogged me from Puerto Rico to Virginia to Alaska and now to St. Louis. Please bear with the following long explanation, but I feel that it's very important to offer some history.

1. PUERTO RICO: Car began overheating after install of Steeda U/D pulleys, GT40P heads, Precision Products 75mm TB, Crane 1.7 RR and Ford E-303 cam by Puerto Rican mustang speed shop in January ‘03. EGR capped, emissions hoses removed. Thermostat removed due to immediate overheating. Ran okay for a few months, then began running very hot. Discovered fan wasn’t operating correctly…not coming on at all. Fan motor (HI/LO) tested out fine. Replaced water pump, TPS, brake booster, master cylinder, battery, MAF with C&L 76mm MAF system; and added 24 lb injectors, Accufab adjustable fuel pressure regulator, and installed Fluidyne radiator. Shipped car to Virginia.

2. VIRGINIA: In March ’04, car “diagnosed” with a blown head gasket by a reputable Mustang speed shop in Norfolk VA, so tired engine was ultimately replaced with a fresh 306, ported/polished Typhoon U/L intake, PI Stallion 2800 stall converter, custom subframes and a 180 stat. Still ran hot. ECT connector unplugged by speed shop in order to force (HI/LO???) fan to run all the time. Fan does not come on with ECT connector plugged in, so plug connector was (and still is) left disconnected. Oil pressure reads very high, and it occasionally pegs the gauge, but car didn’t overheat. Drove x-country from Virginia Beach, VA to Bellingham, WA, and had to run with the heater on to keep the car from overheating at highway speeds in August ’04.

3. ALASKA: Installed 160 degree stat (’05)...although I hear this isn't a good stat for a 5.0Ldue how cool it runs, replaced alternator (’05), ECT (May ’06) and CCRM (May ’06). ECT connector voltage measurement was fine, and ECT sensor checked out fine. Car ran very cool (“O” in NORMAL) most of the time. Then, in April ’06, car ran hot and overheating. Ford Dealer diagnosed problem and found leaking “manifold(???)” by a/c compressor; dealer that said that the ECT was bad and that the fan AND compressor will not work if A/C system is discharged…??? $400 later, they replaced the ECT and charged the A/C system. A/C blew cold. They also recommend replacing the leaking “manifold” for another couple hundred bucks. Shipped car to St. Louis with intentions of getting a second opinion.

4. ST. LOUIS: Car overheated when picked up from military VPC (August ’06). Fan wasn’t spinning. Fan worked better the next day and for the next couple of weeks. A/C blowing hot air, so added refrigerant to the system and drove car 100 miles round trip to friend’s house. Had to run heater to keep car from overheating, but fans was running.

Car suddenly started running hot and overheating a few weeks later (couple of days ago); no refrigerant in the system and fan not running. Tried to recharge, but leaking at HI pressure AND LO pressure Schrader valves! Jumpered the LPS connector to run the A/C compressor while charging the A/C system: no joy. Verified that when ECT connector is plugged in, fan runs for a few moments, then cuts off.

5. Really not to worried about the A/C, but will test voltage at LPS connector and A/C compressor connector; and will also install valves when I get access to a meter and some tools. The main thing is the fan.

I’ve been following this forum for over 3 years seeing what others are doing to combat similar issues. Thanks to Hissin5.0, I’m seriously considering running the DC Controller so that I don’t have to worry about a switch to run the fan on high. http://www.dccontrol.com/

6. My questions are:
(1) why does the fan run for about 15-20 seconds, then stop when I plug in the ECT connector, even with the A/C system charged?
(2) does the A/C system have to be properly charged in order for the A/C compressor to run when the LPS connector is jumpered? In my case, I used a paper clip to loop the 2 contacts in the connector.
(3) was the Ford dealer in Alaska correct when he stated that the fan and A/C compressor will not work if the A/C system is not charged? If so, what’s up with the so-called A/C delete kit? Wouldn’t deleting the A/C system cause the fan NOT to work?
(4) Does the LO fan or HI fan run when the ECT connector is disconnected? I'm hoping the answer is the LO fan, which would explain why the car runs hot while I'm cruising on the higher, forcing me to run the heater to help dissipate some heat.

I am now at my wits end. I am definitely a poster child for dumping way too much money into chasing this problem. I will appreciate any and all observations and advice.

 

[HISSIN50]

Welcome! What an entrance! I probably have come across a thesis or two that was shorter.

I like the path of your travels - not unlike places I've lived. It's great to see some different places.

I might have missed something, so bear with me. For your questions:

1).The fan was a bit of a TSB/recall issue. The bearings could seize, which could contribute to your issue, though you arent blowing the fuse. Just something to remember. I'd really recommend an aftermarket temp gauge or a means of interpolating the ECT temps (if the ECT readings are known to be calibrated, which at this point, I'm not sure we know). Look for low speed to come on at 208*F.

2). Nope, jumping the LPS should engage the AC clutch (as bad as it is to do that). If you dont have juice makin it to the clutch, but you know the clutch locks up (it's not an issue with the electromagnetic clutch itself), check the WOT relay at the CCRM.

3). Both speeds of the fan works irregardless of AC or not.

4). WIth an open in the ECT signal return (like disconnecting the ECT connector), the EDF relay control should indeed turn on Low speed. It does this as a safeguard because without ECT input, the computer has no idea what temps the motor is at. Better to run the fan than not.

You have the upgraded radiator . I think I saw something about a chip in your sig. Did you have them turn down the fan thresholds (so low and high come on sooner)?

I can vouch for Baskin's (DC Controller). The unit rocks! I went to it because [after much chasing] I found my PCM was not switching the CCRM input for the low speed fan off and turning on high when AC was on.

You could rig up manual fan switches. I ran those for a while.

Post up what was not addressed - that was a long read.

Welcome again and good luck!

 

[306DropTop]

Thanx 4 the quick response Hissin5.0. Of all of the places I've lived, I enjoy the Pacific Northwest the best. Well, sounds like I've got at least 2 separate problems: fan and A/C.

I'm starting to suspect that my PCM may be part of the problem since I've change out just about everything else. The fan was changed out in August of '02. Any suggestions for an aftermarket replacement? I wasn't aware of a TSB/recall issue. The Ford dealership here won't touch the car due to the liability of working on a modified Mustang...or so they say.

Glad to hear that it is the LO fan speed that is activated when the ECT connector is disconnected. That explains the lack of adequate heat dissipation under spirited driving conditions or hot days above 80 degrees.

I'm going to forego the switches and install the DC Controller and go back to a 180 stat. I do have the SCT module, but I'm not sure if the fan speeds were recalibrated. I'll have to find someone around here to check the settings in it for the fan and everything else it affects. It probably won't make much of a difference once I install the DC Controller, but I still want to know for peace of mind.

After work today, I'll check voltages at the LPS and the A/C compressor connector. If the WOT relay is located in the CCRM, then I'm less inclined to think that is the culprit since the CCRM was replaced back in May and the fan problem didn't go away...however, I'm fully aware that just because the CCRM is new doesn't mean it still isn't bad.

More later...

 

[HISSIN50]

The stock fan is pretty decent. And the DC controller has its own circuit protection (I just talked to Brian Baskin earlier today about this very issue. If I understood him correctly, the Dc Control unit has something like a sense-circuit which protects it if there's a short. You can ask him for yourself (or simply ask him if it's ok if I Forward [to you] the information he sent me - it'd save him some typing). I like your thinking regarding getting that controller.

If you do want another fan (I'd likely just keep yours), SPAL makes nice low profile units, and the 3.8L Taurus fan is nice and very comparable to ours (without the shorting issues, AFAIK).

If you swap stats, I'd grab a Mr Gasket 180*F unit. It makes generic parts store T-stats look like poop.

I hear ya about the CCRM. It's kind of a pain. If you do have a WOT relay issue, that's one relay in the CCRM that I would not mind working around (installing a stand-alone relay in its place). As you know, all the CCRM is, is 4 or 5 relays in a box.

Let us know how the LPS and AC clutch comparison goes. You have the system charged up, no? If not, the LPS should not pass any voltage.

Good luck.

 

[urban96]

i feel your pain. i was having the same issues.. sort of.

last summer and the summer before once and a while my car would overheat (well just get too warm for my liking.)

but it was doing wierd things. like it would get warm if i didnt have a/c on. but then with a/c on it would stay at 210.

then this summer something happen and it didnt wanna stay down at 210 with or without a/c on. i tried rigging up a manual fan switch but had no luck

i ended up buying a spal fan controller much like the one mentioned. pretty simple hookup IMO and you can just tap into the stock ECT sensor. you can also use it with your stock fan (just wire it to the high speed side of the fan)

got it for around $75 on ebay. http://cgi.ebay.com/ebaymotors/SPAL...020QQitemZ300022237188QQrdZ1QQsspagenameZWDVW

i set low speed for 160 and high for 205

car usually sits around 200. 180 if im at idle for a while or its cool out

 

[306DropTop]

Hey Urban96, did the SPAL come with all of the wires and fuses long enough to connect to the ECT, a/c compressor and battery, or did you have to provide your own?

 

[306DropTop]

Great news! I got a wild hair and wiggled the wires to my radiator fan and it came on LO fan speed with the ECT connector unplugged. It still doesn't come on with the ECT connector plugged in, but now I know that the fan does operate as it should under these conditions.


I went to Autozone and borrowed a multimeter and checked the LPS connector...incorrectly. Once I got back to the hotel I'm temporarily staying in pending closing on my house on Monday, I realized that I tested across both leads in the connector (1.2V) instead of checking each lead to ground to see which one yielded 12V, so I'm going to guess that one lead of the connector actually was putting out 12V, and the other would have read negligible voltage. Due to my "faulty" indication of 1.2V, I neglected to check the a/c compressor's connector. Looks like I'll be making another trip back to Autozone tomorrow to verify this since they're now closed. If I'm correct, I'll see 12V at the LPS. Then I'll take a look at the a/c compressor connector.

Question 1: in my original post, I mentioned that after my new motor was installed, my oil pressure read high to the point of pegging the needle occasionally. What would cause this?

Question 2: I must also add that my stock battery voltage gauge reads really low, very close to the 8V while idling at a stop, enough to cause my CD player to stop temporarily until I tap the gas, or resume driving. Underdrive pulleys or...??? Would my disconnected ECT connector affect this?

 

[HISSIN50]

Great news! I got a wild hair and wiggled the wires to my radiator fan and it came on LO fan speed with the ECT connector unplugged. It still doesn't come on with the ECT connector plugged in, but now I know that the fan does operate as it should under these conditions.


I went to Autozone and borrowed a multimeter and checked the LPS connector...incorrectly. Once I got back to the hotel I'm temporarily staying in pending closing on my house on Monday, I realized that I tested across both leads in the connector (1.2V) instead of checking each lead to ground to see which one yielded 12V, so I'm going to guess that one lead of the connector actually was putting out 12V, and the other would have read negligible voltage. Due to my "faulty" indication of 1.2V, I neglected to check the a/c compressor's connector. Looks like I'll be making another trip back to Autozone tomorrow to verify this since they're now closed. If I'm correct, I'll see 12V at the LPS. Then I'll take a look at the a/c compressor connector.

Question 1: in my original post, I mentioned that after my new motor was installed, my oil pressure read high to the point of pegging the needle occasionally. What would cause this?

Question 2: I must also add that my stock battery voltage gauge reads really low, very close to the 8V while idling at a stop, enough to cause my CD player to stop temporarily until I tap the gas, or resume driving. Underdrive pulleys or...??? Would my disconnected ECT connector affect this?

You really only need a test light for this. If there's a Harbor Freight nearby, test lights go for a buck on sale, and meters for 4 bucks on sale (I have good stuff and those, and use those cheapies often. When I break one, I dont ).

Getting decent aftermarket gauges is the way to know what's up. Do you know what bypass rating they used on your oil pump? STock is just over 60 PSIG as I recall. A chafed sender wire or a bad sender could cause high readings. Even a cheap parts store mechanical oil pressure gauge hooked up for a day (leave it sittin on the passenger seat or something) will tell you where you are at, and kind of allow you to 'calibrate' your stock gauge. I'd worry a little if you're really seeing pressure that high (worrying about the oil filter, etc).

The volts issue sounds more plausable (it's not that the gauge is horribly off, but there is a bonafide issue). When volts drop, you lose the dash clock, CD player and somethin else that I cant think of right now.

If your idle is truly low, you can turn the idle stop screw in. If your idle is decent (700 RPM+), you can put an OD pulley on the alternator. In my case, I chose to raise the idle up. U/D's wont help this, if you have them. I have all stock pulleys.

The ECT would have nothin to do with this.

Good luck.

 

[urban96]

Hey Urban96, did the SPAL come with all of the wires and fuses long enough to connect to the ECT, a/c compressor and battery, or did you have to provide your own?

yup all wires were long enough. i mounted the box in the engine bay on the fender behind my CAI. if you mounted it in the cab you might need to add some wire.

 

[306DropTop]

Thanx Urban!

Hissin5.0, Haynes is a fairly good manual, but I'm learning very quickly that it doesn't cover everything. From reading another recent post that you responded to from another 'Stanger with a turbo who is chasing an ECT problem as well, I'm going to check the resistance on the wire running between the ECT and the PCM. Each time I that I checked the unplugged ECT connector (the last time being this past May when I replaced the ECT sensor), I got a reading of 5V on one wire, zero volts on the other wire. I know that the circuit isn't open, because the fan doesn't continuously run at LO speed with the connector in, so it just may be a resistance issue like you indicated. As a last resort, if the wiring and the ECT connector are good, then I'll purchase the fan controller.

Great idea about installing an overdrive pulley for my alternator! I haven't touched the oil pump or oil sender cuz I don't know where they are, but would guess that they're close to the oil filter) , so I can only assume that it retains the stock 60 psig calibration.

Question: Where are the oil pump and oil sender located? How do I check them?

 

[HISSIN50]

Thanx Urban!

Hissin5.0, Haynes is a fairly good manual, but I'm learning very quickly that it doesn't cover everything. From reading another recent post that you responded to from another 'Stanger with a turbo who is chasing an ECT problem as well, I'm going to check the resistance on the wire running between the ECT and the PCM. Each time I that I checked the unplugged ECT connector (the last time being this past May when I replaced the ECT sensor), I got a reading of 5V on one wire, zero volts on the other wire. I know that the circuit isn't open, because the fan doesn't continuously run at LO speed with the connector in, so it just may be a resistance issue like you indicated. As a last resort, if the wiring and the ECT connector are good, then I'll purchase the fan controller.

Great idea about installing an overdrive pulley for my alternator! I haven't touched the oil pump or oil sender cuz I don't know where they are, but would guess that they're close to the oil filter) , so I can only assume that it retains the stock 60 psig calibration.

Question: Where are the oil pump and oil sender located? How do I check them?

If you have the stock pump (you'd have to pull the oil pan to access it - not something you want to do), the oil pressure sender is quite possible.


You're right - it's above the oil filter. It's a dinky little bulb lookin thing (I think the body of mine was tan color). You can replace the sender and/or add an aftermarket oil pressure gauge with the use of a Tee fitting (so the stock gauge continues to function).

I personally would add an aftermarket gauge no matter what, even if it means having a dead stocker (for now - till you're moved in). Most of us just replace the sending unit on the stocker - I don't have a clue what the calibration of it is - wait, that's because it really doesn't have any. If tossing a new sender at the issue doesnt help, we add a real gauge.

Good luck on this and the closing of your house!

 

[urban96]

also it dosent hurt to add another ground strap from the engine block to the chasis. the stock one is pretty small and gets corroded over time

 

[306DropTop]

More great news! I figured out why my a/c compressor wasn't working. I noticed that my clock wasn't illuminating in the pod on top of my dash, so I checked my owner's manual for the location and rating of the fuse. Turns out that the same fuse controls the power to the a/c compressor clutch. The compressor ran fine and the clock illuminated after replacing a 15A fuse. I still have a slow leak in the a/c system that I have to track down, the a/c doesn't blow very cold, and the gauge on my can of R134a repetitiously cycles from green to blue to yellow indicating that something odd is happening, but at least now I don't have to worry about replacing the compressor. I'm now comfortable with having a vacuum test performed.

Will follow up with more results once I test the ECT wiring and connector, check the engine-to-chassis ground, replace the engine oil pressure sender, and install an overdrive pulley on the alternator.

 

[HISSIN50]

The AC low pressure gauge fluctuates because your AC clutch is engaging and disengaging. WHen engaged, the reading is lower (and is what you need to know). When the clutch disengages, the system wanders towards equilibrium, with the low side pressure floating up towards 100 PSI.

Good luck.

 

[306DropTop]

Back again after a long layoff. Jumped back into troubleshooting my cooling fan issue.

1. Disconnected ECT connector and tested continuity. It read "open": good.
2. Disconnected 60 pin connector from PCM and jumpered pins 7 and 46. Tested continuity. It read "short": good.
3. Installed SCT module in PCM, reconnected 60 pin connector, re-attached connector to ECT sensor, replaced 160 stat with a used 180 stat that opens at 205-210 degrees (tested it by boiling it on the stove with a thermometer), and re-attached negative battery cable. Started and warmed up engine, and wiggled ECT connector wiring: fan came on low when the dash temp gauge needle reached the A in NORMAL. Drove around town at varying speeds: thermostat opened a little late, but low fan came on when the dash temp gauge needle reached the A in NORMAL.

I consider this a mild success. I neglected to check the HI fan operation by turning the A/C on HI, so that will be next in order to verify proper ECT/cooling fan operation.

I still need to check engine block/chassis grounding strap to see if it's causing the low battery voltage and high oil pressure readings. Depending on the results, I may or may not be installing an overdrive pulley and replacing the oil pressure sending unit, then I should be done! Almost there....

 

[RIO5.0]

I still need to check engine block/chassis grounding strap to see if it's causing the low battery voltage and high oil pressure readings. Depending on the results, I may or may not be installing an overdrive pulley and replacing the oil pressure sending unit, then I should be done! Almost there....

After reading this it brings back memories....As mentioned I would remove that ground strap to the block and replace it..It can look fine but not be working correctly, clean the area where the other side of that strap connects to the inner fender...the entire set-up can oxidize or time... and that stud set-up on the block has multiple nuts and the Neg battery cable in the mix..those conditions would contribute to your wacky gage readings...
How old is that battery?? I found my battery being on its last leg and that ground were causing my issues..same as yours hi/low readings...
And as Hissin mentioned, some real gages are really needed to verfiy whats going on.. the stockers....well they leave something to be desired if your trying to verify issues against what they read...