RotaryPower27

So anyway as some of you know i have been having lots of probs with my swap. So today i went through every fuse and relay and checked them all and somehow got it to start again. After starting it, it ran like crap. So i went over all my hoses and stuff and found that i forgot to plug the MAF in. I plug it in and bam same as before no spark no injectors. What is the deal im guessing that the MAF is bad and with it being unplugged is making it run crappy. P.S. It idles fine, a little sputtering, but when i give it gas it tries to die. Just thought i would add that info in. Thanks in advance

Kenteth

When the MAF senses no air, the fuel relay shuts off. Its to shut off fuel from flowing everywhere causing a fire in an accident. When its unplugged, it may go to a default, thus making the fail-safe not so safe...

Does kinda sound like the MAF is sol hearing that. Get the FSM and chech the pinouts on the MAF to be sure.

RotaryPower27

Well i have a straigt 12v going to the fuel pump so no shut off on that. But the MAF shouldt shut down the EGI system right? I thought it just killed the pump.

Kenteth

EGI is fuel injection, it will definately shut it down stock. If yourun wiring that bypasses the MAF fail-safe (hope you never get in an accident) this shouldn't be an issue.

Check the MAF per the FSM and post the results.

WAYNE88N/A

What is the deal with everybodys' AFMs all of a sudden breaking on an engine change? There's gotta be something going on here that we haven't figured out yet...Another rx7 mystery, yeahhh

Kenteth

Yeah, just like how everyone's DP starts to leak or catch on fire within the same two weeks... Its crazy voodoo around here sometimes

RotaryPower27

Please dont jinx me i have had enough problems just getting this damn thing to start.

Kenteth

Well if this is the 89, you're safe from the DP trolls anyhow...

NZConvertible

Personally I think the AFM gets blamed far too often, maybe because people assume they must be complicated. These are incredibly simple devices that are equally simple to check. If you stick a voltmeter on the output wire you should get a voltage that falls as the flap is opened and rises as it closes. The FSM is your friend...

WAYNE88N/A

There's a reason they get blamed too often- because they actually are the culprit at least 50% of the time this particular problem pops up (and I think I'm being very conservative with that 50% figure).

How many threads have we seen (that actually come to a conclusion, lol) in the past 6 months that follow the same story line- the engine is changed, or rebuilt and reinstalled, everything's put back together, and bam- car won't start, or starts and dies...At least 2 or 3 that I can remember (And I've killed the majority of my memory brain cells over the course of my life, starting in high school ,lol) were bad AFMs...

What are we doing to these things? Are we not leveling them enough on reinstall? Are we "dropping" them on the workbench (or worse yet, concrete floor) when we remove them, perhaps shocking them enough to break the (16 year-old) wiper-to-potentiometer connection? Something is going on....

I'm beginning to sound like a broken record here- read the AFM's output from the ECU, or at the very leeast remove the AFM's plug, and read the pins out per the FSM...Like NZ said

RotaryPower27

Well everyone was right the AFM had a connection come loose so i re-soldered it and now the car starts with it pluged in, but its still running crappy. I spent the whole day going over the vacum lines and everything is plugged in. It just doesnt accelerate at all, takes awhile to get it going. Any suggestions on adjusting the trottle body or where to look next would be great.

WAYNE88N/A

I'm sorry I keep repeating this guys, but...

If you have absolutely no clue why the car is running like ****, read everything out from the ECU, per the FSM...

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/troubleshooting-your-car-ecu-340578/

DerangedHermit

No reason to be sorry. I'm never sorry when I post up a reply saying "Do a search." Ya know why? Because it's the best answer that can be given under the circumstances. I have yet to read everything out myself, going to do that this weekend. I'll let ya know how it works for me.

RotaryPower27

For your information Kermit i have done the ecu check, right now im asking for any other suggestions. I really wish people on here would stop refering to the search button. Yea tell it to a person if he is constantly asking questions that have been answered a hundred time. In my case i dont think i was. I thought the point of this forum was for the rotory brains to help out the little people just getting started. It people like you that make me want to junk the damn thing.

DerangedHermit

You never said you did the ECU troubleshooting. If you haven't stated it, it's assumed that it hasn't been done.

My comment about the search button was not directed at you.

What the hell do you think Wayne was doing when he made his comment, messing with your head trying to make you explode your car?

WAYNE88N/A

OK, if you've already accomplished the ECU input checks, and everything was good, that narrows the list of suspects down considerably...It can't be your main relay, or your CAS, AFM, TPS, ignition timing signals, etc...

However, it could still be your timing, or your plugs/wires, or serious vac leaks, or clogged injectors, or bad injector connectors, etc...

We help when we can...Don't take it for granted

RotaryPower27

no i know wayne was helping me as he has done previously. But your reply was neither helpfull nor did it have anything to do with the thread. My whole problem was you chimed in with a smart *** remark. If you wanna bitch to people about not searching start a thread about it. Thats all. For those that want to help me...One last peice of info. When starting the car i have to damn near keep the pedal floored and it takes about 10 seconds for it to finnaly fire. I have been and stil am searching for answers but they all go back to problems that i have already checked. Im just seeing if anyone has a shot in the dark as to the problem. Thanks and sorry for whining.

RotaryPower27

The TPS, should it go all the way back in when the throttle is release or only about half way. I looked at that today but couldnt see any way of adjusting it to push back any further.

RotaryPower27

sorry to keep it up, but i just wanted to say that i took one of the vacume lines off i think it was the one going to the pressure sensor, it changed nothing in the idle but it had a pretty strong vacume it seemed. Just wanted to throw that in

WAYNE88N/A

Yes, the plunger will "stick out" some, as you put it. In any case, if you were getting your 1 volt at the ECU during the checks, you're good for now...

If she runs really rough when you finally get her started, start looking at an injector problem. Go back to the ECU, and read out your primaries, one at a time, with her running. The voltage should drop to about 13.5 at idle, assuming your alternator is putting out 14 to 14.5 or so. Record the voltage readings of the two injectors with just key on, then record the readings at idle. If there is no change in voltage between the two key positions, that's your bad injector- it's not "firing". Could be the injector, could be the wiring. Probably not the ground, though...

RotaryPower27

no actually after it starts i get a great idle. its just when i get in and hit the accelerator it doesnt rev likes its supposed to really slow. And when i took it around the block it was driving like i was pulling a damn trailer behind it. The real problem is just the slow acceleration. once it gets goin it goes, untill i shift and put a load on it again. I hope im being clear enough. Thanks for all your help

WAYNE88N/A

Yeh, you're being clear, but it would have been nice to have all of this pertinent info up front...

Clogged cat, clogged fuel filter?

Any hesitations? Or just no power?

RotaryPower27

just no power. at all

WAYNE88N/A

When is the last time you had the injectors cleaned & tested?

When is the last time you changed the spark plugs? Plug wires?

When is the last time you cleaned or replaced the air filter?

Are you using more gas than normal?

RotaryPower27

tommorrow im gonna go and change everything out filters and stuff. Where around here could i take those injectors to be cleaned, (no mechanic around here will go near my car, thats why its alway do it yourself) or can i clean them my self