Heres the scoop. Ive got a 94 fd twin turbo at. When i got the car it wouldnt run. I did a complete fuel system swap off of another fd, tank and all. That got the car running.

Now, heres the issue, the guy who i bought it from did a poor mans non seq. Eliminated the Rats nest, and redid some vac lines when he did the poor mans. I went back over all the vac lines and fixed two issues. Blew out the map sensor, removed the ecu, reattached it. Hooked everything back up including the battery. Started right up, absolutely no issue. Drove it around for like 20 mins and ran like a champ. Came back home and turned it off. Came back to the car 15 min later, started it up, and it had the bogging/backfire issue at 3k. And its hard to get it up to 3k at that, you have to feather the throttle.

Then i unhooked that battery, blew out the map sensor again, unhooked the ecu, plugged it back in. Hooked up the battery, started the car, no issue. Drove it again just fine.

Turned off the car, the issue came back.

 

I'm assuming you have the stock ECU? If so, check the ECU codes. Sounds like you have something putting the car into limp mode. Do you have resistor on the connectors for the solenoids that have been removed?

 

Yes, i do have the stock ecu.

As far as resistors, i have no clue, ive had the car for two weeks. Practically knew nothing about it until i got it. So, please do go into depth so i can go verify that everything is proper.

I am not however getting a check engine. And i believe its obd I, and nowhere around cant hook it up. I guess i could be wrong.

 

For the ECU, you can check the codes with a wire or paper clip jumping two ports in the diagnostic box:

http://www.fd3s.net/engine_codes.html

Basically, removing some of the turbo controls for the non-seq mod can result in the car going into limp mode if resistors aren't in place of the solenoids (to trick the stock ECU into thinking they are still there). Check the codes first and see if you have any stored, then we can go from there. Not all codes trigger the CEL.

 

Mahjik is totally right. You car seems to be in LIMP home mode. Check your codes, find your problem fix it and battery reset your car =). I had same problem before, would bog, backfire at 3k. But if let go of throttle and slowing going up, I can cruise around 70mph =).

Good luck. Post with updates and result.

-AzEKnightz

 

Okay, so my buddy in my hometown is checking the codes as we speak. I asked him to triple check the codes so that were not trying to fix the wrong thing.

He said the car threw about 12 codes at him, all within the 30 to 50 range. Most of those appear to be solenoid.

If you could please help me out with a picture as to where they are. Im sure they are under the uim, right?

Just walk me through this if ya can =D

 

Check the following link for the solenoid connectors:

https://www.rx7club.com/showpost.php...03&postcount=3

You don't need resistors on all of them however you need to post up all the codes you got so we can make sure you get the "most likely candidates" for your situation.

 

I'd just buy a PFC and be done with it.

 

Definitely in limp mode. Install the 300ohm 1/2 watt resistors, disconnect the battery for about 30 seconds, then hook it back up. Car will run perfectly.

 

So, do you think i should hit up radio shack and try to find some resistors or what? What do you think Mahjik?

 

Well, I think you need to the following:

A) List the codes you have
B) Pick up the resistors from Radio Shack (330 Ohms 1/2 watt)

Some of the solenoids are for emissions, some are for the twin turbo control. The ones for emissions can be ignored.

 

Well sadly my friend insisted that there were too many codes to write down. So, it wont be until this weekend until i can have those up on here.

So let me clear something up, when clearing out the so called rats nest, there are about 6 harness that are eliminated, however you must put resistors on most of them?

 

With a stock ECU yes. Just put the resistors across the connector and electric tape and/or solder them.

 

Put the 330 ohm 1/2 watt resistors in the colorful plugs(7 in a row that went to the row of solenoids). Disconnect negative terminal of battery for 30 seconds, reconnect negative terminal of battery and enjoy the car. Just listen to me, I wont lead you wrong

 

Okay gents, heres the codes, i got them a bit earlier than i thought i would.

25 pressure regulator control solenoid
28 egr solenoid
30 split air bypass solenoid
31 relief 1 solenoid
32 switching solenoid
33 port air bypass solenoid
34 idle speed control solenoid
38 accelerated warmup system and air supply valve solenoid
39 relief 2 solenoid
42 turbo precontrol solenoid
43 wastegate control solenoid
44 turbo control solenoid
45 charge control solenoid
46 charge relief control solenoid
50 double throttle control solenoid

 

Just install the resistors, codes will still be stored and show up even with the resistors installed but the car will no longer go into limp mode.

 

Well i can only find the 8 that are under the upper intake manifold, and i didnt notice any "colorful" harnesses. Explain which prongs go into which pin.

 

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/wont-start-no-spark-829608/

Look at the picture in that thread, it is the row of connector starting with the orange one near the top of the picture. They are the ones that connect to all the solenoids in the "rats nest"

 

25 pressure regulator control solenoid
34 idle speed control solenoid
42 turbo precontrol solenoid
43 wastegate control solenoid
44 turbo control solenoid
45 charge control solenoid
46 charge relief control solenoid
50 double throttle control solenoid

Those would be the main ones to be concerned with... I assume you have a manual or aftermarket boost controller?

 

I have no boost controller yet. I should be getting one within the next week or so. Why?

 

It appears you have eliminated the wastegate solenoid.

 

i didnt, the previous owner did.

uhh, so what do i do to fix it, and will the car run?

Because its running off of one wastegate, for non seq.

 

I'm running a PFC but I get a very similiar problem with stuttering/hesitating/backfiring at ~3k RPM if I only apply half-throttle.

Under very light throttle and full throttle, I have no problems...

Relation between my problem and the OP's?

 

Nope, the PFC could care less what you delete, as far as I know it has no limp mode.

 

The car only has one wastegate:

http://www.autosportracetech.com/RX-...erOverview.htm

What should you do? Either purchase a used wastegate solenoid or an aftermarket electronic boost controller. I would suggest the latter.