Liquid_Cure

So recently, my check engine light came on, and off, and on. 3 months prior I replaced, the headgasket, and surfaced the head, replaced the valves, replaced the header, and all the other stuff that goes along with replacing a head gasket. I drove it to the store today, when I came out it wouldnt start. I replaced the wires, cap and rotor. Nothing. I replaced the CPS, Now it did start and it does run, but it seems like the hard start is getting worse over time, and it will idle rough reguardless of how long I've ago I drove it. So it has a new, CPS, Wires, Cap, Rotor, Air Filters Clean.

One thing I did notice is that when it wouldn't start I checked the battery terminals to see if they were lose even though they were cranking, and the negative one was, very very hot. it cooled down and hasan't got warm since. Its seems like im giving it alot of water, But I did a compression test and it seems, fine, Does anyone know the proper PSI for a the 4.0 Liter for a 97. Any idea's what to do? or Check?

Shade133

compression should be around 130-140 and all cylinders should be within 5psi would be optimal.

fuel pressure should be 37psi

and if your negetive terminal got hot. theres a huge issue at hand. most likely a short issue. check all your wires and grounds. make sure none of them are cut or corroded or loose.

firstime00XJ

Double check the ground that is on the backside of the motor that attaches to the firewall...should be in the center.

Liquid_Cure

I checked all the wiring, looks good, the compression was right around 140, so that's good too, haven't checked the fuel pressure yet, it also didn't start today again, but then started later, checked the wiring sequence, it's good. I'm starting to think it's a fuel problem, where should I start? Could it be bad gas? I can't find a fuel filter!

Liquid_Cure

Checked that! Good and tight! Thank you.

MulishaXJman

What about a fuel pump with an itermittent short or maybe it's shot? The B cable is going to get hot if you keep cranking it. I would'nt worry about that. Check your V+ at the pump and go from there.


ps. Run it out of a bucket of fuel and see if your problem goes away, if not check for pin holes in your supply line...Let me know what you find.

Shade133

fuel filter is usually mounted on the frame behind the driver rear seat on the driver side. its a big round object with fuel lines coming in and out of it.

if there isnt one there or anywhere to be seen. buy one, splice the line and put it in.

now id say check the fuel pump ballast resistor for good connections. if they seem tight and non coroded. then the next time you have a issue of it starting but dying or not running correctly unplug the 2 connections and bypass the resistor. only do this for a short period of time. the resistor is there for a reason. after the vehicle is started and your not in wide open throttle the ballast resistor lowers the voltage to the fuel pump to keep it cool.

ive had a lot of issues and found my resistor was going bad. i replaced it with a junk yard one i had laying around and now so far 200 miles later ive had no issues.

Liquid_Cure

This is very frustrating, the problem is getting worse the idle is really bad, and I keep throwing misfire codes on every cylinder, I checked my fuel pressure its good. Both my o2 sensors appear to be clean, its overheating now, but will only get to like 220 and wont get warmer there is condensation coming out of the exhaust when I start it, but once it warms up it stops, doesnt smell like antifreeze, but im not entirely sure there is any left since I have to keep adding water all the signs point to the head gasket again, which I have just replaced recently. I don't know what to do, low on money and I find myself under the hood frustrated.

If its misfiring would that make the engine overheat?

Why does the temperature change from 190 to 220 so fast, At a coming up to a stop light its 190, by the time its green its 220.

And why is the rough idle intermittent?

Im very frustrtrated at this point. and to make it worse my transmission seems to be on its last leg.

Shade133

ouch man..

did you have your head gasket replaced by a shop or did you do it yourself?

DRHouse822

On a 97 that was the first year that they put the fuel filter in the tank, you have to pull the sending unit in order to get at it. The condensation in the tail pipe when the vehicle is cold, is normal. Is there (excessive) white smoke coming from the exhaust, that indicates burning coolant. Check your overflow, is it overflowing due to a bad radiator cap. I can tell you on my 97 Cherokee and 06 Wrangler my overflow is always at "add" if i top it off to full it just disappears, but never ever drops below add. This is the same on my brothers 98 Cherokee and 05 Wrangler. For the problem with 190 to 220, let the jeep idle up to temp and see if your aux fan comes on this should happen no hotter 200, if it dont check your connections and your aux fan temp switch. also if you have ac turn it on when you get to a street light, this will turn on your aux fan assembly immediately, and see if this keeps your temp down.

Liquid_Cure

I did it myself, I followed every step, in replacing it, and had a few people help me, also Im ou here looking at it, misfire on 1 & 5 they fire at the same time 1s plug is clean, looks normal, 5 has oil on it, piston rings, valve seal. I hope it's neither, could it be anything else!?!? Also the PVC valve on the valve cover closest to the firewall (vacum), has a white residue inside of it, is this normal?

And if it is either of those things, why would it be intemittent Reguardless of temp?

Liquid_Cure

the smoke isn't excessive and dies off after running for a few minutes. The fan seems to go on at the appropriate temp, and I think it may just have been low on coolant it seems to be staying at a normal temp now. The only thing I hope is that it's not a head gasket or a piston ring, Im not sure if I really want to do that again, plus, I can not afford it.

DRHouse822

The 97 still ran a cap and rotor distributor, so it is impossible for it to fire two cylinders due to mechanical issues that's good news for you. ? are you using the factory spark plug wire guides, if not it is possible that wires 1 and 5 are crossing each other causing both plugs to fire this can happen even if the spark plug wires are not frayed. If it is this, it would be intermittent due to fact if the wires move just a little it will cease to cross fire. Now for the PCV Valve, the 4.0 never ran a PCV it ran a CCV Valve, which is a fancy way for saying "open tube". I grew up back East and just like Sacramento there is a lot of moisture in the air, this will mix with oil vapor in the CCV tube forming a thick milky type residue. On the early 4.0 it would saturate your air filter with in 15000 miles, due to the fact the larger of the two breathers goes in to the air box.

DRHouse822

With the jeep COLD, open the rad cap and start it up, do you see air bubbles. What I think is happening the cooling system is pressurized so when the engine is shut off and hot it is bleeding coolant into the cylinders and that is why the white smoke is dying off after running for a few minutes. The issue however is the fact that with the engine running the cylinders are putting out more pressure than the cooling system, forcing air into it system. This can force the rad cap open causing your overflow to flood leaving you with out enough coolant in the engine, and if the rad cap don't open it can grenade your radiator.

DRHouse822

I meant to say the milky residue is normal and wont harm the engine.