The Vert is running wicked rich, I swapped the injectors back to N/A injectors from the T2's I was running. The car backfires between every shift and shoots flames like nutz. The flames are cool and all but it's making my bumper alll black. My Gas mileage is horrible and the car reeks like semi-burnt fuel.. HELP!!

Current setup:

Blocked off ACV
Unplugged BAC (should I go ahead and block it too? I have the Blockoff)
TPS set right on at 1k ohms and sweeps clean
Timing right on the money
5th and 6th sleeves removed
Egr plugged off but not blocked off. (have that too)

Car needs assistance idling for about 20 seconds then does good, but it will change idle speed at each stoplight... Any suggestions would be most helpful.

 

Sounds like a sensor is malfunctioning. Any codes yet?

 

My car was doing the same thing about a week ago. Found a vac leak, fixed it and now its back to normal.

 

injector leaking

 

when you say "change idle speed at each stoplight" do you mean at one light it is at 700 rpm and the next it is at 900??

Or that its is surging???

 

What you said first, Icemark. He mentioned in another thread how it picks its idle when it stops. Sometimes 400, sometimes 750, sometimes 1500.

 

Goofy is right, it will idle great at 800rpm I will drive for 10 minutes and hit a stop sign, it will idle at 400rpm then I will drive 10 feet put the clutch in for the next traffic signal and it will sit at 900rpm.. I thought Vacume leak too but have yet to find one. Almost everything is blocked off anyways with Vinyl Nips. I am going to read the codes, I totally forgot about that..lol..

 

Read the codes, nothing there.. Ugg.

 

What sensors should I go checking?

 

check the throttle position sensor or TPS

 

Hum, how is the dashpot? It working?

How did you adjust idle?

Did you set it by adjusting throttle cable tension or by the screws?

James

 

You say you removed the ACV...you don't still have your cats do you? They could be terribly clogged by now.

 

i know this is crazy, but thermowax piston on the TB? I did the TB mod and no more wicked crazy idle. Its a T2, i know, but maybe you could wire the 2ndary throttle plates open and see, when i took my thermowax off, there was residue like wax all in it. I know, this is pretty far off base, but i would agree that possibly the dashpot or something with the TB. Maybe check the accelerator cable to see if it isnt sticking partially, or that its not too tight. BTW, i know this is a total threadjack, but once the BAC is removed, and the screw on the TB is set all the way in, how can one adjust the idle up?

 

i have a 87 tII that i just bought.... its doing the same thing... would also like some info on this

 

I set the Idle by waming the car up to temp, adjusting the top mix screw all the way down (almost), Set the TPS while the car was off (to 1k ohms), Then adjusted the tension to hone the idle to 800rpm. The car is timed perfect to the "T" and it purrrrs..

It is still crazy rich. The idle situation seems to have fixed itself (may have been the old gas in the tank) so I am going to try and change the plugs and see if it works any better. I am having the mufflers done Saturday morning. The exhaust is still not bolted up all the way at the manifold so I doubt the cats are the issue (plus it only has one now)

I will keep screwing with the settings and see what happens, the funny thing is i can lean it out with the idle mix screw (on the fenderwell) and it will choke it down a tad but it will still burn your eyes at idle. Oh I also have no air pump...


I am not familiar with the "dashpot" what is that, where is it located and what does it do?

Thanks for the info so far, I am trying everything.. This car is running better then any other 7 I have owned.. Out of 18 that is pretty durn good.....

 

Bad or unplugged O2 sensor perhaps? My car was flaming big time when I bought it, then I found the O2 sensor unplugged. I bought a new one (autozone $35) and it made a big difference.

 

My sensor is hooked up, although the wire was laying on the manifold so maybe it got a little burnt.. I will attempt to rewire it, although it was my understanding that the O2 sensor had little to no bearing on idle, it was more after 2500rpm.. Dunno worth a shot.

 

If there is an exhaust leak before the O2 sensor, the air/fuelmixture will be wrong. If it sees too much oxygen, the ECU will add more fuel.

Gordon
WitchHunter Performance

 

Well the exhaust is unbolted right where it is supposed to hook up to the manifold, it is bolted to the block though.. the o2 sensor is on the manifold, so it probably isn't getting any oxygen before the sensor, but after tommorrow morning I will troubleshoot this some more as the exhaust will be all bolted up by 8:30am on Saturday..

 

Get that bitch running so I can fab some roll bars!!!!

 

It goes in Tommorrow morning at 7:30am for the exhaust, and then it will need some fresh gas and a little premix.. She's up and driving.. call or PM me to arrange a time for you to get to work on it!!!

 

The dashpot prevents backfiring and bad behavior when you let off the gas.

Any backfiring and stuff when you let off the gas?


James

 

Being as stock O2 sensor is narrowband...wouldn't it only be effective BELOW 3000 rpm or so?

With mine, unplugged / cut..it ran MUCH richer all the time. I got like 10 mpg...

 

Well just got back from the exhaust shop, they built me a sweet 2 1/2 in downpipe (N/A) And hooked up the mufflers. I have a wicked exhaust leak where the manifold meets the block, SO I have to pull it loose and check the gasket, and rebolt it up.. oh well maybe that's why it's running crazy rich the O2 isn't reading right.

 

I had a simlar problem once, turned out I accendently connected the MAP sensor to a bad vac source.. so the car thought I was 100% load so it would back fire like crazy.

Hope that helps.