4gze bog down

Kevin mr2 1985 · 06-07-2009, 10:32 PM

okay i have no idea why but my mr2 that has a swapped levin gtz 4agze bogs down when you just floor it, but if you eas on to it you get going pritty dam fast.... i have no idea why please help! also the cold start sucks i always have to give it some gas to start it any ideas on that too?

Ideas of whats wrong:
NA mr2 exhaust
no o2 sensor

palos · 06-07-2009, 11:17 PM

Two initial possibilities: (1) Perhaps there is too much tension on the butterfly valve in the AFM; (2) Perhaps incorrect ignition timing.

Kevin mr2 1985 · 06-08-2009, 12:23 AM

well it is MAP sensor and coil packs'

also i checked engine codes and what would make it say that air to fuel ratio is off. and also where is the vacuum sensor?

Jackstand Queen · 06-08-2009, 10:40 PM

Did you ever get the h-temp VSV hooked up to the Fuel Pressure Regulator? If you don't have the VSV, you could just shortcut over from the intake manifold barb, straight to the FPR.

I don't know what your MAP (manifold absolute pressure) sensor looks like, or where it would mount. But it should be small, mostly plastic, and have an electrical connector and one vacuum line to it. A lot of MAP sensors I've seen are mounted on the firewall, and not on the motor.

These are two likely candidates for your lean condition code. Knowing your car's history, you've gone through the fuel system top to bottom . . . so its probably not the cause.

Kevin mr2 1985 · 06-09-2009, 12:21 AM

lol well i guess a 255lph fuel pump wouldn't hurt... lol its stock fuel system
also i know im supposed to get a 255lph but what install kit?

Jackstand Queen · 06-09-2009, 02:16 AM

Did I just read you have no O2 sensor installed?

This sensor is vital to the EFI.

If defective, or not hooked up . . . its another one of those items that will cause the motor to run in dumbed down mode. Lack of O2 sensor will cause the engine to run rich. Also, without it, the ECU cannot determine whether the mix is rich or lean. Therefore, throw out your ECU's error code, if you have no O2 sensor.

06-07-2009, 10:32 PM	#1 (permalink)
Kevin mr2 1985 it started! yes! Join Date: Mar 2008 Location: Washington Posts: 424 Thanks: 0 Thanked 2 Times in 2 Posts iTrader Rating: (0/0% )	4gze bog down okay i have no idea why but my mr2 that has a swapped levin gtz 4agze bogs down when you just floor it, but if you eas on to it you get going pritty dam fast.... i have no idea why please help! also the cold start sucks i always have to give it some gas to start it any ideas on that too? Ideas of whats wrong: NA mr2 exhaust no o2 sensor

06-08-2009, 12:23 AM	#3 (permalink)
Kevin mr2 1985 it started! yes! Join Date: Mar 2008 Location: Washington Posts: 424 Thanks: 0 Thanked 2 Times in 2 Posts iTrader Rating: (0/0% )	well it is MAP sensor and coil packs' also i checked engine codes and what would make it say that air to fuel ratio is off. and also where is the vacuum sensor? Last edited by Kevin mr2 1985; 06-08-2009 at 05:45 PM.

06-08-2009, 10:40 PM	#4 (permalink)
Jackstand Queen Cage Fighter Join Date: May 2008 Posts: 677 Thanks: 52 Thanked 56 Times in 53 Posts iTrader Rating: (1/100% )	bogs . . . but it runs Did you ever get the h-temp VSV hooked up to the Fuel Pressure Regulator? If you don't have the VSV, you could just shortcut over from the intake manifold barb, straight to the FPR. I don't know what your MAP (manifold absolute pressure) sensor looks like, or where it would mount. But it should be small, mostly plastic, and have an electrical connector and one vacuum line to it. A lot of MAP sensors I've seen are mounted on the firewall, and not on the motor. These are two likely candidates for your lean condition code. Knowing your car's history, you've gone through the fuel system top to bottom . . . so its probably not the cause.

06-09-2009, 12:21 AM	#5 (permalink)
Kevin mr2 1985 it started! yes! Join Date: Mar 2008 Location: Washington Posts: 424 Thanks: 0 Thanked 2 Times in 2 Posts iTrader Rating: (0/0% )	lol well i guess a 255lph fuel pump wouldn't hurt... lol its stock fuel system also i know im supposed to get a 255lph but what install kit? Last edited by Kevin mr2 1985; 06-09-2009 at 12:44 AM.

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06-07-2009, 11:17 PM	#2 (permalink)
palos … Join Date: Apr 2009 Posts: 170 Thanks: 0 Thanked 20 Times in 18 Posts iTrader Rating: (0/0% )	Two initial possibilities: (1) Perhaps there is too much tension on the butterfly valve in the AFM; (2) Perhaps incorrect ignition timing.

06-09-2009, 02:16 AM	#6 (permalink)
Jackstand Queen Cage Fighter Join Date: May 2008 Posts: 677 Thanks: 52 Thanked 56 Times in 53 Posts iTrader Rating: (1/100% )	Did I just read you have no O2 sensor installed? This sensor is vital to the EFI. If defective, or not hooked up . . . its another one of those items that will cause the motor to run in dumbed down mode. Lack of O2 sensor will cause the engine to run rich. Also, without it, the ECU cannot determine whether the mix is rich or lean. Therefore, throw out your ECU's error code, if you have no O2 sensor.