I hooked a scanner to my rig and it says error 34 MAF or Circut voltage low??? does this mean I Need a new MAF???

 

Maybe, but probably not. I'd try the relays and cleaning the connections, reset the computer and see what you get. Most of the time it's a dead relay.

 

both relays new and painless harness new.

 

Check the connections, it wouldn't be the first time a pin had been bent in the maf housing. If not, then I'd look to see if Vader's post on testing the MAF is still kicking around somewhere.

 

Code 34 is very seldom the MAF sensor itself failing. A misadjusted or malfunctioning TPS will cause a code 34, also another culprit believe it or not is leaking injectors. Test your TPS voltage first and let us know what the readings are. Also put a fuel presure gauge on the test port on the rail and let us know how fast your fuel pressure bleeds down.

I fought a code 34 for a year before I figured it out. Turned out mine was caused by the injectors leaking.

Do some testing and post the results and we will see if we can help you track it down.

 

TPS is 3.8 volts not sure on fuel pres yet

 

also it says o2 lean

 

Anything else that came up? It's typically nice to list everythig before you have people start trying to help.

 

thats all but the tps voltage was 3.4 not 3.8

 

finally got my psi guage back and i have 39 psi at idle and 49 at full but when i shut off the engine and the pump quits it immediatly 0's. is there any way to tell which injector is the culprit? thinking about changing all 8...cheaply any suggestions???

 

If it immedatiely goes to zero then your injectors are defintiely leaking. Do not even bother trying to just replace one. Buy a new set of Ford Motorsport injectors from Summit for 200 bucks and be done with it. As soon as you replace one another will go bad. Just by the new set.

The car will run much better and if it is bleeding down that fast you can be guarenteed that more then one of them is leaking. This will probably take care of the code 34 problem also. That is actually what my car was doing when I had a code 34.

 

Pull the plugs, they'll tell you whick ones are leaking.

 

You're unnecesarily making life difficult for yourself. Perform a more complete diagnosis, and find the problems. Speculation about what might or might not cause what is irrelevant. You've already found some facts, now just find a few more and put them together for a diagnosis:

1. A TPS voltage of 3.4 or 3.8 at idle is incorrect. There should be no more than 0.62VDC from the TPS with a closed throttle. Something there is amiss, and the high TPS voltage is the reason the MAF error is being generated. The ECM monitors engine RPM, throttle opening, and compares that to a table that defines minmum and maximum intake air flows for those parameters. If the MAF output voltage is not within the limits, an error will be generated. The whole process takes about 600mS.
2. If you believe you have injector performance problems, you may be able to isolate a leaking, blocked, or streaming injector(s) by performing a power balance test. Removing and inspecting the plugs for a rich condition may be beneficial, but I'm suspecting that you will see rich mixture indications in every cylinder due to your low oxygen sensor error and the resultant default rich mixture.
3. The fuel pressure dropping to 0 immediately after shutdown may be due to a leaking injector. It may also be due to a leaking FPR, a failing check valve in the pump, or a combination of any of those.
4. A MAF low signal error should not necessarily also cause a lean O² sensor error. If anything, the mixture should go rich once the ECM enters Backup Fuel Mode after the MAF error is generated. I'd suspect you have other problems with either the O² sensor itself, or air leakage into the exhaust on the left bank.
5. If your scanner cannot report what the ECM is seeing as MAF intake flow in g/S, throw it in the trash. It is nothing more than a glorified paper clip. Get out your voltmeter and read the output voltage directly at the MAF with the engine warmed and running at idle. Note the engine RPM with a real tachometer, not the one next to the speedometer. The MAF should produce in the range of 0.750-0.950VDC at a normal idle of 800-900 RPM. If it is not, you have either leakage in the intake ductwork, incorrectly routed PCV or CCV lines, a leak into the crankcase (such as a breather type oil filler cap), a major vacuum leak (such as a brake booster), low line voltage to the MAF, a dirty MAF hot wire, missing MAF screens or cooling fins, or lastly a failing MAF sensor itself.

 

thanks...I'm TPI illiterate! the scanner we used was a snap on but I'm not sure we know what we're doing.

 

A SnapOn scanner (at least those I've looked at) should be able to get data from the ECM and display the g/S reading. If you don't have the scanner instructions, a voltmeter will work just fine.

 

OK...this is where we stand...Ive bought some ford performance injectors but they are shorter then my old injectors??? there are 2 slots for the clips and if I use the top one the injector will go in the intake the same depth as the old ones but will they be deep enough in the fuel rail??? is this common? will they still work or did I get the wrong ones ? I also found a huge vacuum leak on the intake.

 

The "huge vacuum leak" explains the MAF error code you were getting, and the lean error code, and probably a few other nuisance problems.

The overall length of the injectors is not as important as the length between the 'O' ring grooves. Those need to be identical, or within about a millimeter. Also, you need to use the GM style 'O' rings instead of the smaller cross-section pieces that were probably delivered with the injectors. Clips are optional, and are really only there as an aid to assembly.

 

I was afraid of that. I have the wrong injectors. the grooves are about the thickness of the o-ring shorter. which ford injectors do I need?

 

That might be within a millimeter or so. You can trial fit one or a few on one side of hte rail and see if they have enough length to fully "bury" the 'O' rings. If so, that should be all that's necessary for a good seal.

 

its about 3mm and if i put the clips in the top slot they go deep in the intake but i dont think they are deep enough in the fuel rail

 

If you bought ford motorsport injectors which are all the same lenght they will fit and seal just fine. There are hundreds of people on this board running them. Myself included.