99 wrangler hard start

Mine takes about 1.5 seconds to start every time, and has since new. It is a 95. Yours sounds like a different problem though. There is a check valve somewhere in the fuel system that can leak down. Buy or rent a pressure gauge to put on the fuel rail and see if this is it.

What do you mean "doesnt get great gas mileage"? If you got the big engine, of course you're not going to get great mileage. If you got the small engine, you won't either. Mine has the small engine and gets about 25 mpg after a bored out throttle body, high performance exhaust and electric cooling fan. Before all those upgrades it got about 20. If you plan to take it off road, you can wait on the exhaust upgrade, until after you smash your current muffler on a rock, heh, heh.

You of course gave it a complete ignition tune up, air cleaner, etc.?

Welcome to the club.

Earle

battery termials are probably dirty. As for gas mileage, realize you bought a brick on wheels.

Carl

magicman proclaimed:

If you can get it to start quickly by turning the key on, wait 5 seconds, turn the key off, then start, your fuel system is losing pressure. If it happens mostly overnight, not to worry.

As for the mileage: it is roughly as aerodynamic as a brick. It is geared for offroad.

Could you elaborate on the bored out throttle body? I have a 04 with 4.0 and am looking for ways to increse the milege. Just finished the air cleaner, electric fan, and exhaust ( cat back ) upgrades, but havent gone anywhere to check milege. Taking a trip next week to see. Thanks Tom

It's just the stock 4.0 TB that's been oversized. The end result is it will flow more air. This of course does no good at all if the rest of the system (intake rail, head, exhaust system) can't flow that much.

course Hesco is't the only place to get one, and it is possibleto make one yourself (if you have milling tools).

Likely a drop in fuel pressure when it sits for a while. If it starts immediately when warm, this is probably it. Leaky fuel injectors or check valves in the fuel return line or regulator (depending on design) are suspect. A worn out fuel pump will also cause this.

Some makers during some years program the PCM to delay the ignition system for a few revolutions of the engine to help circulate oil into the top end of an overhead camshaft setup before allowing the engine to fire. I seriously doubt this design applies here, but I think it's a good idea no matter. AFAIK, DC does not use this logic in any of their cars.

Great fuel mileage isn't something you'll see featured on a Jeep product. They're heavy trucks with engines of vintage design; my TJL weighs nearly 2 tons empty, and around town I manage 18 mpg, and about

20 on the highway. Driving habits and proper tire pressures affect this the most. I'm perfectly happy with 18 mpg; most of the 4WD Chevy-guys around here average 6-8 mpg. around town; one Expedition owner I know averages only 4 mpg! I used to own a crappy old '68 Dodge Polara 440 that only got 3 mpg, city or highway. You could do worse.

A bored out t/body will do nothing for fuel economy. It won't help performance either, other than at wide open throttle.

It goes without saying that if you're "enjoying" your "performance increase" from a larger t/body, you're not gonna get any fuel mileage.

These are average figures, but I went from about 20 mpg in stock configuration to about 25 mpg after the bored out throttle body, cat back exhaust and electric fan. This was with the 2.5 liter engine. I believe that in the stock configuration, the vehicle runs a little rich in order to keep NOx emissions down. Most modern vehicles doo. According to spark plug appearance, the vehicle isn't running too lean now, but the gas mileage is improved, according to measurements made over 7 years. In my experience I couldn't measure or evaluate the alleged performance increase I was supposed to get, but the mileage increase is very real. The fact that you might believe this to be impossible doesn't change the figures I have written down in the notebook I keep in the vehicle.

One thing about the fan. The four cylinder engine doesn't need as much cooling air as the six, so I can drive down a highway or even a gravel road and it will never come on. Usually, the fan only comes on in the summer in city driving. That is why it represents a fuel savings, because it doesn't have to come on and therefore use engine power. Your six cylinder experience here may be different.

Now if you put in at least a cat-back exhaust, which sooner or later you will have to replace because of rocks, rust, whatever, well it seems to have helped the Jeep and the Suburban I have too. And you can't argue with the cool sound it makes.

Earle

Your fan swap probably did more to increase fuel mileage than anything else; belt-driven fans soak up a lot of energy.

They're attention-getters, but they don't make more power or burn fuel more efficiently. I'll pass on the extra attention; I get enough from local cops and thieves as it is.

Thanks Earl The electric fan is working out well. The only comparison I have so far is the RPMs Have dropped at a given speed so it should work out

Tom

No way to tell, but this is a good combination. With fuel prices the way they have been, I might have made back the money I spent on this stuff.

No way to tell, except by putting it on a dyno. I am going on the general principle that "more air, is better".

Felices Navidades.

Earle

There you go again, really really....

Felices Navidades.

Earle

I think that's the next mod for my ZJ.

Read about some of it here.

Although I want to hook up a thermostat and a cutout switch. Anyone know of a site that has that setup for the ZJ.. actually it doesn't have to be a ZJ as wiring is going to be the same reguardless of the engine/fan.

The fact the Ford 8C607 drops in makes it very tempting. Nothing like a mod you can back out of if it has problems. :)

i had a similar problem on my 97. If it's the fuel pressure system (which it sounds like) shoot me a message and I can walk you thru the steps to fixing it. A good way to test if its a fuel problem is to turn the key to the 'on' position a couple of times and not start it. After

3 or 4 times see if it starts easy. If it does, that means that you have an issue with maintaining fuel pressure.

And mpg....i get 15.5....it ain't a hybrid

No doubt, the fan probably made the biggest difference. The exhaust may have helped too. However, I was addressing the t/body. It will not change fuel mileage, or mixture. For that matter, nothing you did will affect mixture, since the PCM will adjust to get the O2 content of the exhaust where it wants it.

Under load conditions, the PCM will shut down the fuel to adjust to the restrictive stock intake and exhaust. That is what you are saying. Maybe I'm getting more mileage, which we know for sure, because I am actually getting more power. What you're doing is invoking theory to try to prove that the throttle body is useless, but automotive design is not 100% theory. Most of it is testing, testing and more testing.

Earle

i can turn the key onece w/o starting it and it cranks up right up o the second key turn ?? th

-- magicman