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Delayed acceleration

Reply #16 –
Is the engine code in your VIN a 4 ? This would be the 8th digit in the number.

Delayed acceleration

Reply #17 –
Yes, that is what I assumed was the EVP. RockAuto lists that same exact part as the EVP though, at http://www.rockauto.com/catalog/raframecatalog.php?carcode=1140286&parttype=5092&a=FRc1140286k1113896 and I could not find an illustration of it on jcassity's EVTM link, and the only mention of the EVP was on page 69. I also just checked my VECI and the EVP is not mentioned there. I just took some pics so you can tell me if I am just blind or if my engine is some abomination of ford. http://s34.photobucket.com/albums/d130/badkarate/cougar/

Edit: Yes, the 8th vin digit is 4.

Delayed acceleration

Reply #18 –
You definitley have a PFE sensor. RockAuto has it misnamed.
Engine code 4 is 3.8L SEFI engine. You have a more modern engine than all the earlier 3.8L Fox body T-Birds and Cougars.

VECI...Vehicle emissions control information? What book do you have?

Here is the error code info for Taurus with engine code 4. This is from a Chilton's manual.

KOEO(Key on, engine off):
....On demand codes;
........34 Defective PFE sensor
....Continuous memory codes;
........32 EGR valve not seated
........34 Excessive exhaust backpressure
........41 Right HEGO shows lean or no switching

KOER(key on. engine running):
........32 EGR not seated
........34 Excessive exhaust backpressure
........41 Right HEGO shows lean

Delayed acceleration

Reply #19 –
Did the 88 3.8 come with one HEGO sensor or two?
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Delayed acceleration

Reply #20 –
There is only 1 HEGO sensor that I know of, and I replaced it about a year ago. The VECI placard I am referring to is on the top of the fan shroud. So if I'm getting this right, the KOEO method is pulling a currently defective PFE sensor, while the not seated EGR and backpressure are from the memory. Since I replaced the EGR when I found out it was bad, that should take care of that code. The HEGO is good, since it's detecting that it's running rich. What's throwing me off is why would the PFE test bad on KOEO but not on the KOER?

Delayed acceleration

Reply #21 –
Quote
The HEGO is good, since it's detecting that it's running rich


Every EEC-IV I can think of shows code 41 as a lean and/or not operating properly code.

Test the o2 sensor and wires:  Shown is 4 pins......Test is similar for 3 pins
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Delayed acceleration

Reply #22 –
"
Quote from: badkarate;243002
Just finished pulling codes again. KOER method pulled a 41 again, I waited about 10 minutes and there were no other codes. KOEO method pulled a 34 then a 32, waited about 5 minutes this time and no more codes so I assumed it was finished. This was done after replacing the EGR so I'm going to check out the EVP next.


The KOEO test has two parts. The first part runs tests on the sensors and reports the results of the tests. These codes are called "on demand" codes. No errors are a code 11. All codes are presented twice.

The second part reads out codes that were stored in the memory of the EEC. While you are driving a "Continuous Self-Test" is running. If it detects a problem it stores a "continuous memory code" in the EEC.

I can't tell from your post which catagory the codes are in. An on demand code 34 means a defective PFE. A memory code 34 means excessive backpressure.

After the on demand codes there is a 6-9 second gap then a single seperator pulse followed by another 6-9 second gap then the memory codes start.

On demand codes and KOER codes are solid failures. Memory codes can be intermittents that happen while you are driving. No telling how old the memory codes are. If you take the jumper off while the memory codes are reading out, it will reset them. Run KOEO again to make sure they are gone. Keep checking to see if they crop-up again.

As for the HEGO code 41, if you only have one sensor it's for the one you have. If you have two it's for the right(passenger side) sensor. The earlier CFI 3.8's have two sensors.
Just because you get a code it doesn't have to mean the sensor is bad. You could be running lean for some reason.

Delayed acceleration

Reply #23 –
Quote
You could be running lean for some reason.



Which is why he should test the sensor and wires ;) Then maybe some simple fuel supply tests....
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Delayed acceleration

Reply #24 –
I think the problem may have just fixed itself, but I'm trying not to get too excited. I went out to pull codes, so I started the car to let it warm up. Died at the first two starts, then tried again and held the gas for a few minutes. I let off the gas and the idle smoothed completely out, but I went on until it was at running temp. Did the KOEO test first, pulled a 34 then an 11. Next to the KOER, it only pulled a 41 this time. I should probably mention that last night, I remembered an old girlfriends POS Suzuki, that in order to reset the computer you left the battery disconnected for 5 minutes. I decided to do this over night, if not for anything else but to see if it would clear the memory codes. I went ahead and tried to test the 02 sensor, but either my volt meter just shiznit itself, or the 02 sensor is bad. Got power from the pigtail that plugs into the sensor, but nothing from the sensor itself, even ohm wise. I'm going to let it cool down, then try it again, see if it does it again or if the problem is actually fixed.

Delayed acceleration

Reply #25 –
You checked the resistance at the sensor at room temp?
-- 05 Mustang GT-Whipplecharged !!
--87 5.0 Trick Flow Heads & Intake - Custom Cam - Many other goodies...3100Lbs...Low12's!

Delayed acceleration

Reply #26 –
No, I did not, that would probably be why the resistance was reading off then. I'll have to pull it to test it at room temp, since the constant here is about 43 outside. I'll post results when I do it.

Delayed acceleration

Reply #27 –
Quote from: badkarate;243483
Did the KOEO test first, pulled a 34 then an 11.

Sounds like you are saying you have an "on demand" code 34 and a memory code 11. Is that correct?

Quote
I should probably mention that last night, I remembered an old girlfriends POS Suzuki, that in order to reset the computer you left the battery disconnected for 5 minutes.

Yes that is another way to reset the memory codes. It also resets some other stuff in the computer, so it may idle py for 4-5 minutes until the computer reestablishes it's data.

Quote
I went ahead and tried to test the 02 sensor, but either my volt meter just shiznit itself, or the 02 sensor is bad. Got power from the pigtail that plugs into the sensor, but nothing from the sensor itself, even ohm wise. I'm going to let it cool down, then try it again, see if it does it again or if the problem is actually fixed.

Can you be specific about which pins you had your meter probes on.

Delayed acceleration

Reply #28 –
Quote from: badkarate;243374
Mine is the 3.8, so no worries about checking into everything 5.0 related..


your 3.8 is different from the 87 3.8 and more like the 5.0 with respect to vac solenoids.

Delayed acceleration

Reply #29 –
I am still going to encourage a simple fuel presure test as well.

this is a huge delay we are talking about ,, should be power / perfromance related as well.

is there a delay in passing gear?

I am so sorry for posting about that EGR EVP sensor.  You have no idea how bad i feel on this.  You do not have the sensor mounted atop the EGR at all.

However, you do have a green vac line and that vac source needs verified by tracing it back to its source.  If it goes to a vac solenoid, everythng i said still applies for the EGR Solenoid.