Ex tries to die when warm. At a loss.

[T_JARDING]

Hey everybody this Is my first post here so i hope its in the right place.

Im gonna try to start from the beginning so yall know what im dealing with. I bought my 93 ex about 6 months ago. It ran like a dream for a few weeks. Until i had to replace the fuel pump, filter, and regulator. Then for a few months it ran great. Within the past week ive noticed a horrible loss in low end power. About a day or so after that i was on my way home from work when it wouldnt hardly rev past 1000rpms at all. If i let off the gas it would try to stall out and die. It ran really rough and sounded awful. So i went through and checked all my air components. IAC,MAF, checked for vac leaks, checked TPS, everything seemed to be good but the issue persisted. I pulled my cats off on advice from a long time ford mechanic. Still hasnt changed. My next lead is to go through and check plugs wires and coil pack despite them all looking fairly new. Omw to work today it did the same thing, but while sitting in traffic amongst its horrible erratic idle, it evened out and my power came back for a very short while any advice would be much appreciated and thank you in advance.

 

[Centaurious]

Pull the codes, here is a site with info. It doesn't say it but you can read the flashes from the Check Engine light.

http://www.troublecodes.net/ford/eectest/

Once you have the KOEO, CM, and KOER codes you have clues to what is going on.

 

[T_JARDING]

Sorry i forgot to mention that but there is no CEL this time around which to me is pretty baffling. Can it throw codes without a CEL?

 

[Rhett]

Sorry i forgot to mention that but there is no CEL this time around which to me is pretty baffling. Can it throw codes without a CEL?

A CEL (check engine light) is a "thrown code"...

It's possible that there are some stored codes in the computer memory, which a KOEO (key off engine off) test would show. A place like AutoZone can read codes for free. I'd start there first as Centaurus says, so you know where you stand.

Without knowing anything...make sure your battery cable connections are tight...particularly look at the wire-to-alternator connections. Could also be a bad cable, in which case when it craps out you are running straight off the battery, and when it "kicks in" and runs well, you're getting good connection. I say all of that, because a failing or loose cable will not necessarily throw a code.

 

[Turdle]

Engine Coolant temperature Sensor --and or low coolant. I'd change the ECT


The 2 wire sensor is the one in question. The other coolant sensor is just for the guage.

 

[T_JARDING]

Noted guys thank you. Ill look into the ECT and ill go through and check all my battery connections and update when i find anything out.

 

[2stroke]

Do you think it's running rich or lean? Lean smells more pungent, while rich smells sweet, or like raw gas if its bad enough. Does the exhaust have black goo in it? The first thing that came to my mind is an O2 sensor, but without a code or a proper scan tool, that doesn't give you much to go on. I would definitely do a fuel pressure test, even if your pump is newer. Also pull the vacuum line off the fuel pressure regulator, and see if it has gas in it. It will be more evident when running.

 

[T_JARDING]

Do you think it's running rich or lean? Lean smells more pungent, while rich smells sweet, or like raw gas if its bad enough. Does the exhaust have black goo in it? The first thing that came to my mind is an O2 sensor, but without a code or a proper scan tool, that doesn't give you much to go on. I would definitely do a fuel pressure test, even if your pump is newer. Also pull the vacuum line off the fuel pressure regulator, and see if it has gas in it. It will be more evident when running.

If i had to guess i would say its running rich? You can definitely smell strong exhaust but cant say forsure rather rich or lean. I will be getting the fuel pressure tester on it this weekend. I checked my coolant as per advice earlier and my reservoir was bone dry. So i filled it up and tried burping the system after work. Will also pull the regulator like to check for gas. Replaced that a few months ago with a junkyard one. Maybe gone bad?

 

[T_JARDING]

Engine Coolant temperature Sensor --and or low coolant. I'd change the ECT


The 2 wire sensor is the one in question. The other coolant sensor is just for the guage.

Do you have a decent diagram of the ECT location? I couldnt find a good one online. Thanks

 

[T_JARDING]

A CEL (check engine light) is a "thrown code"...

It's possible that there are some stored codes in the computer memory, which a KOEO (key off engine off) test would show. A place like AutoZone can read codes for free. I'd start there first as Centaurus says, so you know where you stand.

Without knowing anything...make sure your battery cable connections are tight...particularly look at the wire-to-alternator connections. Could also be a bad cable, in which case when it craps out you are running straight off the battery, and when it "kicks in" and runs well, you're getting good connection. I say all of that, because a failing or loose cable will not necessarily throw a code.

All my connections were good including alternator. Im gonna get over to auto zone this weekend. Last time i asked them to read codes for my pre 96 they said they couldnt?

 

[Turdle]

Do you have a decent diagram of the ECT location? I couldnt find a good one online. Thanks

This picture should help. The sender circled on the left, with 2 wires is the coolant temp sensor which PCM uses to adjust fuel ratios

The one on the right, with one wire, is for the gauge. ignore it.

If your coolant was low this would explain a lot of things. No coolant on the sensor means the PCM does not know what to do, then the engine revs a little and coolant gets pumped to the sensor and the pcm adjusts.

Also, if there is not coolant on the sensor ( low coolant) , or hotter than expected coolant the PCM will try to rev the engine and dump in excess fuel to cool things off.

I suggest finding the coolant leak. Could be as simple as a clog in the reservoir return hose output nipple in the reservoir. a clog here will allow flow out but not back in

If a head gasket or cracked head is suspect, pull the spark plugs, lay them out in order and post a picture of them. If coolant is being burned it will show on the spark plugs

 

[T_JARDING]

This picture should help. The sender circled on the left, with 2 wires is the coolant temp sensor which PCM uses to adjust fuel ratios

The one on the right, with one wire, is for the gauge. ignore it.

View attachment 151053

If your coolant was low this would explain a lot of things. No coolant on the sensor means the PCM does not know what to do, then the engine revs a little and coolant gets pumped to the sensor and the pcm adjusts.

Also, if there is not coolant on the sensor ( low coolant) , or hotter than expected coolant the PCM will try to rev the engine and dump in excess fuel to cool things off.

I suggest finding the coolant leak. Could be as simple as a clog in the reservoir return hose output nipple in the reservoir. a clog here will allow flow out but not back in

If a head gasket or cracked head is suspect, pull the spark plugs, lay them out in order and post a picture of them. If coolant is being burned it will show on the spark plugs

ok awesome! I did check my coolant return line for a clog and there was nothing there. Ill pull my plugs this weekend and try to check my sensor before then. Upon further inspection last night i noticed what appeared to be dried coolant on the outside of the radiator right below where the radiator cap is. Maybe the leak is there??

 

[T_JARDING]

Hey all i got a video today of my problem conditons as i got hme from work. All week ive drove with my heater on to pull heat from the engine bay. Today i did not and my problem returned. Coincidence? Also check my radiator again to find what was a black papery substance around the top ring. Any ideas? Maybe causing a clog somewhere? Also i cant seem to upload the video to those interested.

 

[T_JARDING]

This picture should help. The sender circled on the left, with 2 wires is the coolant temp sensor which PCM uses to adjust fuel ratios

The one on the right, with one wire, is for the gauge. ignore it.

View attachment 151053

If your coolant was low this would explain a lot of things. No coolant on the sensor means the PCM does not know what to do, then the engine revs a little and coolant gets pumped to the sensor and the pcm adjusts.

Also, if there is not coolant on the sensor ( low coolant) , or hotter than expected coolant the PCM will try to rev the engine and dump in excess fuel to cool things off.

I suggest finding the coolant leak. Could be as simple as a clog in the reservoir return hose output nipple in the reservoir. a clog here will allow flow out but not back in

If a head gasket or cracked head is suspect, pull the spark plugs, lay them out in order and post a picture of them. If coolant is being burned it will show on the spark plugs

So i found out i have a leak on the top line right below the radiator cap. Its leaks at the connection.