Hey, looking for some help here, 2 times in the past week my non cc carbed 84 z28 camaro has stalled on me after getting off the highway, not sure what the problem is, its not over heating and the only way it will start is if I put the peddle all the way down to the floor and crank it at the same time, then it runs rough for couple seconds and smoothes back out but it seems after the car has stalled the exhaust starts to sound really deep and muggy kinda feels like loss of power also... any idea what my problem is? Thanks

 

Bump, I have this same problem... Have you figured it out? Or anyone else any tips?

 

Hey, actually no I have not, it only started to do this after I had the car at a shop for a lean condition, they changed my jets and tuned the air/fuel mixture, my guess is that its flooding because it will not start again after it has stalled unless I hold the gas down wot and start it, the shop is far and just haven't had time to go back but maybe its running to rich now is my guess...

 

if its really hot outside the possibly exists that it could be vapor lock.
it happens with carb engines.
the fuel lines get so hot that the gas doesnt make it to the engine.

atleast i think thats how it works.

 

Vapor lock is caused by heated fuel lines. Vaporized fuel gets trapped in the sealed lines between the pump and float valve. You can understand it better if you study the relationship between the spring loaded pump diaphram and the float valve. Since your car started this behavior after a jet change, it is possible that they damaged or misaligned the float valve causing the float bowl to over flow after extended periods at highway speed, or damaged the power valve causing it to bleed fuel. You don't say what carb you have. Since it's not CC, it obviously isn't stock.

 

Yes it is a stock non CC qjet from an 84 z28, I had vapour lock problem before because lines were too close to headers but had that fixed years back this is new and I'm sure Carb related... I'm in the market for a new qjet but not sure were to get a good quality one that hasn't been hacked on...

 

As far as I know, there was no stock non CCC q-jet in 84. Unless it came on a truck. All light duty vehicles from 82 on were CCC(computer command control). May have been different in Canada. That makes no difference really. Before I scrapped the carb, I would find out why it's dumping fuel. The q-jet uses a combined metering rod/power enrichment valve on the primaries. It uses an air valve to control fuel to the secondaries. I have seen the secondary air valve stick open, causing fuel to be fed into the secondaries even after the throttle is released. The phenolic cam that acts on the secondary metering rods can be damaged too. The most common cause that I see for q-jets dumping fuel is that the phenolic float swells from years of submersion in fuel and stocks against the side of the float bowl.

As far as finding a good reman Q-jet goes, Holley does remans of almost every carb there is. I have worked with their reman q-jets before and they do a good job.

 

Thanks, yes its in Canada.. but I'm just tired of dumping money into this Carb, I've heard mixed feelings on the Holley reman's but I still want to stick with a qjet!

 

I have had good results with all of the Holley products I have used. They seem to take care with their reman work. There are several other companies out there that offer reman q-jets. Just avoid the discount house crap. I have had numerous problems with one certain company. Nothing like having to repair a carb you just bought.