When accelerating it bogs down and backfires and hardly has enough power to get to the next gear

Good morning,

The one that sticks out to me as the most plausible is the 76 Code.

I see that you replaced the VAF (MAF) already without any improvement. While you are waiting for the EGR delete kit to arrive, I would be be looking at the wiring to the VAF. Look for broken wires and corroded terminals. IM not sure where you live, but here in Michigan, with the salty winters, they can get bad over time.

Regards
Jon

It is possible but it would be rare.

The next thing would be to trace the wiring between the VAF and the ECU although at present I am unable to supply you with a schematic. I'll try to fix this soon and if I can I will upload the schematic.

Jon

Okay, I have the schematics now.

You will need a multi-meter to perform this test:

Step 1.
Disconnect the MAF (VAF) sensor connector.
With the Key on, Measure the voltage between pin "B" and ground. (Should be 5 volts) If the voltage is correct, Proceed to Step 5

Step 2.
If it is less, than 5 volts, disconnect the PCM connector, then change to the Ohms setting on your meter, and measure the resistance between that same pin (B) and ground. (It should be higher that 10K (10,000 ohms) The higher the better. If the resistance is good proceed to step 3. If you have resistance lower than 10,000 Ohms then you have a short circuit to ground somewhere in the wire.

Step 3.
If the voltage is higher, then you have a short to power (battery) somewhere and you will need to find that short. Proceed to step 5

Step 4.
Check for continuity between the MAF sensor connector pin "B" to pin 90 on the PCM connector. It should read less than 3 ohms. If it reads higher resistance then repair the circuit. Look for broken or frayed wires, corrosion etc.

Step 5.
Check continuity between MAF connector pin "A" to pin 91 on the ECU connector. It should read less than 3 ohms. If it reads higher resistance then repair the circuit. Again, look for broken or frayed wires, corrosion etc. If it reads 3 ohms or less make one more check. Read the resistance between Pin "A" to ground. That reading should be 10K ohms or greater. If not, you have a short circuit on that wire.

Step 6.
Check continuity between MAF connector pin "C" to pin 58 on the ECU connector. It should read less than 3 ohms. If it reads higher resistance then repair the circuit. Again, look for broken or frayed wires, corrosion etc. If it reads 3 ohms or less make one more check. Read the resistance between Pin "C" to ground. That reading should be 10K ohms or greater. If not, you have a short circuit on that wire.

Here are the schematics to help:

Jon

Woops I edited the last entry I made. In step 6 I accidentally wrote pin "a" when I meant Pin "c" it is fixed now.