'89 Daytona TBI - Running rich and popping at idle

Hey all!

I have a 1989 Dodge Daytona ES TBI that I recently just did a timing belt, head gasket, shaved the head, and some upgrades to the valve train on. It runs great other than it runs rich (smells really rich) and it has a slight popping noise at idle. If you rev it up to 4K while at idle, it'll smoke a very very thin white smoke. It doesn't smell like oil, it smells like a lawn mower with choke open.

Timing is all set 100% dead on and ignition is roughly 12 btdc. Installed a new O2 sensor about a year ago (which made it run WAY better than it had before). No CEL or anything, runs fine other than that. I don't notice any water or oil consumption. Brand new EGR valve, which seems to be working correctly. No vacuum leaks that I can tell.

http://<a href="https://www.youtube....yeMnDH2m18</a>

https://www.youtube.com/watch?v=2yeMnDH2m18

I haven't looked at a tbi engine in a long time but do they have a fuel pressure regulator? If they are leaking gas to the vac line it can cause a rich condition.

sounds like a good place to start.

Is the regulator right on top of the injector?

Well, it looks like the regulator on the TBI doesn't have a vacuum port but it wouldn't be a bad idea to put a fuel pressure gauge on it.
http://i272.photobucket.com/albums/j...psqwccpdfj.png

That would be kind of hard, considering the fuel outlet goes directly into the injector, haha.

I haven't looked at a tbi since like 2007. Do they not have a schrader valve to check pressure? If not I'm sure you could tee into the rubber hose that goes from metal fuel line to injector?

That's a good point. I'd have to look. This has almost nothing but rubber fuel hoses to the injector, but I'll see.

sounds like an injector needs cleaning or is sticking. whit smoke generaly means coolant. but can be raw fuel.... rarely.

as soon as you say white smoke i say head gasket though. and with a miss. pull the plugs. smell them.

your miss could be a miss spray or cloggy injector. or it could be a head gasket.


I would suggest running to about a 1/4 of a tank of gas left. and putting in 2 cans of CHEMTOOL B12. and go beat it pretty good a few times. see if it clears up( injector) or if it gets worse (head gasket)

It's got a brand new head gasket it on it, torqued it all to spec and all. I'm just hoping the valve seals, are sealing.

Here's, an album of pics I did to it.

https://goo.gl/photos/RwqtLaqnMe2e75iy7


It did smoke a LOT worse when I first started it up a week or so ago, but I figured that was from having about a gallon of mineral spirits and stuff in the head from when I cleaned it and old unburnt gas in the exhaust. Because this is the head gasket it had been running with for over a year.

http://i.imgur.com/zYKv5zgm.jpg

Hey warlock; Did you find out what was causing your rich idle and popping issue? I have an '89 tona doing the same. I have went over it so much I could bite nails!

Take off the air filter start the car and look into the TB. Make sure the spray pattern is even and that there is no raw fuel dripping from around the injector. You should just see a mist of fuel spraying. There are o-rings on the injector to seal it. When it's really bad you can see it dripping as soon as the pump primes. Happens on the V8s too. The GM TBI setups are the same way and I've seen it a lot on those.

The regulators can leak and add fuel. Check it and the injector O-rings like stated above.

My spray pattern is fine. We found a huge vacuum leak from the PCV system, the check valve was broke open. That reduced some of the popping, but I think it's either:

A. The car drinks a lot of oil for some reason, a 1 hour trip will drink an entire GALLON of oil. But driving around town it will use none. So I have no idea what's up with that. So that could be causing fowling and misfires in the cylinders.

B. When I relapped the valves, I may have not got them right and fuel is blowing around the exhaust valves and detonating. BUT the car does have 170psi across all cylinders, so... Not sure.