Yet another stumbling/stalling thread..No CEL

[Espresso]

Sorry, I havent been around in a while. Been quite busy still fixing the house from the hurricane.
Well, my old problem of stumbling/stalling just came back to light. It hasnt done it in months( since a few weeks after I got it). But has done it twice in a week.
I get no CEL, does it at random times. The first time( Feb 12th) I was at a red light making a big left( HUGE intersection) I took off, got about 100ft & it stalled. After cranking it & it stumbling@ 400ish RPM's it dies, crank it again same thing, except now I can give it gas to keep up the RPM's after about 30 seconds all of a sudden it comes to life. I pull back out into the road & immediatly Pull into the store we were going to ( It stalled right infront of the store). As I pull into the spot & put it in park . It starts doing it again. I said screw it, turned it off & let it sit. After an hour in the store. Come out & it runs fine until today.
I went about 20 miles to go get the cylinder heads for the vette, come back into town & go to the Ford dealership to pick up a hatch striker. As i'm leaving the the parking spot. I pull around a few cars & am about to pull out of the lot, when low & behold...ba dum da da.....stall. I was doing about 5 mph.
This time I cranked it up & it stumbled for about 10 seconds I put my foot into it & it came back to life. I get home & pop the hood. I find POWER STEERING fluid shot out from the pump & all over the underside of the hood( how th ehell that happened I have NO idea).
I dunno... all I know is that it scares me to death, because I have my son in the car & I cant really push the truck if it stalls on the road.
One other thing is that it has HEAVY preignition on 87 octane. Yet no noticable preignition on 89( which I run now).
I do smell fuel under the hood. But nothing is leaking (assured by the Ford tech who did the fuel filter install).

The things I have done or replaced in the last 1 1/2- 2 months include the water pump, upper & lower hoses w/ t-stat, fuel filter, ignition coil, plugs & wires, tires, cleaned the MAF & IAC, seafoamed the engine, & 2.5" magnaflow exhaust( I also replaced the fuel pump & sending unit a while back).
I know the master cylinder is leaking & needs to be replaced, but wont have the $400 to do it until next wensday( I am hesitant of doing it & getting air trapped in the ABS unit).


Thank you all for reading this long winded post. But I need to put it into detail of what is exactly happening.
Any help is greatly appreciated.

 

[prozachappy]

Your not throwing a cel...but did you scan for codes. Don't rely on the cel light, check for stored codes. also things to check...Fuel pressure...especially if your smelling fuel...could be the FPR. your battery cables could also be bad. 1st gens are notorious for corroded cables. This was the sourse of my severe hesitation...bad neg cable causing intermittent loss of power.

 

[Espresso]

I havent checked it for codes yet. But last time this was happening. The dealership did & found none.
I have to go get a analog V meter today( also need a new bulb for my test light).
As for the cables. They are tight & clean.
I'm also checking the fuel pressure today. I noticed the smal got ALOT worse since I put on the 2.5" pipe.
I checked all the injectors & they are within spec. #2 was running VERY lean. But I figured with the bum coil & bad plug wire( it wasnt within spec) that is what caused it. I havent pulled the plugs yet to check them again, but i'm doing it tonignt. It runs TONS better since I did the coil & plug swap, but I still cant run it on 87 octane.

 

[prozachappy]

How strong of a gas smell do you get ? If your smelling it from inside the truck, and stalling that much...gotta be the fuel system. Sounds a lot like your FPR is about gone. Does it take a few cranks before start up ? Is your hesitation more of a stumble...then power, or an overall loss of power ?
Sounds like your headed in the right direction...if checking the fuel pressure/FPR/fuel relay doesn't lead anywhere, I'd check the obvious like 02 sensors, plugs, TPS, and IAC. I'd still get down to autozone though, and have them scan for codes just to see if anything pops up. Keep us posted...
Jason
That 2.5 exhaust pipe isn't gonna cause this....unless they damaged a fuel line or something while installing.
As far as the 87 octane goes...I could never run less than 89 without serious engine ping until I replaced my fuel injectors and clean out all the carbon in the intakes. Now I'm back to 87. Are your fuel injectors original ? I know you said you checked them but this could be something to look at also.

 

[Espresso]

Smal update..I noticed a surge today while going about 40-45 MPH. It was very very slight, but it was there none the less. When I stopped & got to idle I got very uneasy because it felt like it wants to stall. Once again an intermittent problem. It didnt do it all the time.
As for the fuel smell. I used to smell it in the truck, but that was because they
(previous owners) put in a walbro pump & didnt seal the unit properly. Now its just under the hood when I pop it. There is no visable sign of fuel leakage.
It starts on the first crank all the time with no troubles. But has a slight stumble at idle, no hesitation while revving it though. Almost instant throttle response.
There is no hesitation at all never. It either runs fantastic or has the stalling problem
(stumbling/stalling is very rare like I said. hasnt happened since last time).
I was suspect of 1 of the injectors. After all just because they check good doesnt mean they are not clogged. As far as I know they are original( but the engine is not).
I knew the 2.5 wouldnt cause it I just posted that as what I did( you know how we on the forums like a complete list of crap done for proper diag).

As far as carbon goes. I sprayed some degreaser in the cylinders & washed it out with water...LOL, sorry I had to say it. No I didnt do that
I did seafoam it, & clean it out.
I'm going to head to AZ in a few to see if they come up with something.

 

[Espresso]

OK, fuel pressure is @32psi & 41w/ vac disconnected. Kinda low.
I also went to check the codes & got nothing. I went & picked up a code scanner.
(Actron from AZ). It says that if the light stays on & doesnt flash there are problems.

Still looking for problems( broke wires, ect..)....
O'll post back in a bit.

 

[MrShorty]

Those fuel pressure numbers look normal, if I understood them correctly. 32 psi is normal KOER with engine vacuum applied to the regulator. 41 is normal KOEO and normal KOER with no vacuum to FPR.
Now, no codes at all. There's a fault you can sink your teeth into. 1st thing to eliminate is operator error. Review the instructions (I like the set at www.dalidesign.com/hbook/eectest.html) and make sure you are doing it right (test procedure is the same whether you use a code reader or jumper wire/voltmeter).
Once you determine that you are doing it right, then check the wiring between the computer and the self-test connector and the computer's power and ground wires.

 

[Espresso]

MrShorty. I followed that link before & used those directions. I also tried the directions with the scanner( slightly different). I get the same results......Nothing.
I intentionally set a CEL( TPS & EVR. They were easy to get to) I unplugged both of them & the CEL came on. I still couldnt read anything from the scanner. I have tried 5 times & even let it sit connected for over 5 minutes & got nothing. Just a steady light.
Do you know if there is a website that lists the sensors values, so I can test them. I unplugged all the I could & everytime it effected the idle, ect. I listened to all the injectors with the stethoscope & they are firing. Hook up my vac gauge & am pulling 19hg so the vac is good..

But the funny thing is. I hear alot of the people on the forum talk about horrible gas mileage( even with 3.27 gears). After I did the tune up. I'm at 230miles to this tank & I still have a bit over 1/4 tank of fuel. I used to get 240-248 to every 16.4 gallons(15MPG). So I know it's running good. Plenty of power, no hesitation. But it has a crappy idle, wants to stall on decel (It wont though & gets slightly worse as I sit at a light or stop sign). I just dont understand it. I never had something get this good a mileage with these pending( because i'm not sur ewhat is wrong obviously) problems.
Things I can think of are the CPV( canister purge), IAC & MAF, but I dont have the direction on how to check them. I cleaned the IAC last month( but it looked brand new to begin with). Cleaned the MAF at the same time9 it looked brand new also).

One thing I did just go do( as I was here typing I just remembered the CPV test) I stuck my finger on the hose revved it up & nothing no suction at all. I dont think it's working. So i'm going to replace that tomorrow.
I'm going to check the wiring tonight, also going to go back to AZ & use another scanner, as this one might be bad.

 

[MrShorty]

The vehicle repair guides at www.autozone.com have the same information as Chiltons which will have some information about testing sensors
The sample vehicle for the repair manuals at www.alldatadiy.com has been a '93 2WD 4.0 Ranger, so most of that information is usable.
Actron sells a "sensor and ignition module tester" that is essentially a glorified multimeter. You can download the user's manual from their website (www.actron.com) which I find to be a useful resource for understanding how to test most sensors.

You can go test sensors if you want, but, if it were me, I would focus on why you can't get codes. Some reasons you can't get codes (bad computer power/ground, internal fault in the computer) could also explain your driveability problems. Next thing I would probably do is get a wiring diagram, determine the pin assignments for STI, SIG RET, and STO at the computer's 60 pin connector, and perform the self-tests with my jumper wire and voltmeter hooked up at the 60 pin connector to eliminate any wiring faults between the computer and the self-test connector.

 

[Espresso]

More updates. Well today it stalled agian. This time I had me pressure gauge with me. 10 psi at the rail...not good.

Also as for the pin connectors. When I use the jumper wire( described on this site & the link to the site you( MRshorty) gave me the CEL on the dash stays lit. Wouldnt that tell me the wiring to the 60 pin is good?
SO I believe i'm looking at replacing the PCM( ECU in other vehicles) correct?
One funny thing I found was while testing the CEL by unpluggin gthe sensors. It would throw the CEL, BUT if I shut it off & restarted it the CEL WOULD NOT come back on until I replugged & unplugged the connectors again.


Just wen tout to check FP again( after it has been sitting about 40minutes). ZERO pressure. I power up the pump( ON position) & only get 12 PSI pressure( I didnt power up the pump more than once though)

 

[Espresso]

Ok, it takes 4 pump primes to get it to 38 psi( it spikes to 40 & settles @38 regardless of how many times you do it).
I waited 1/2 hour for leakdown & it got to 28 PSI.
So bad regulator & possibly PCM.
Still checking........

 

[MrShorty]

Let's see if I can organize my thoughts.
1) 10 psi at the fuel rail and you can't get anymore when it stalled? Sounds like a problem in fuel delivery.
2) "When I use the jumper wire...the CEL...stays lit" -- Key on engine off without the jumper wire in place, the CEL is supposed to stay on. This suggests to me that somehow, you're not getting a good connection between STI and SIG RET when you hook up the jumper wire.
3) "One funny thing I found was while testing the CEL by unpluggin gthe sensors. It would throw the CEL, BUT if I shut it off & restarted it the CEL WOULD NOT come back on until I replugged & unplugged the connectors again." -- This is interesting. Not sure how to interpret this, but in at least some cases (MAF for example) I would expect the CEL to be on anytime some of the sensors were unplugged.
4) "Just wen tout to check FP again( after it has been sitting about 40minutes). ZERO pressure. I power up the pump( ON position) & only get 12 PSI pressure( I didnt power up the pump more than once though)...Ok, it takes 4 pump primes to get it to 38 psi( it spikes to 40 & settles @38 regardless of how many times you do it).
I waited 1/2 hour for leakdown & it got to 28 PSI." -- Sounds normal to me. Next time, it's easier to pressurize the rail by grounding the fuel pump test lead in the self-test connector (short end of trapezoid) than cycling the key repeatedly. Spec on the leakdown check is 2 psi/3 minutes. You're losing 10 psi/30 min = 1 psi/3 min, so that's withing spec. It appears to me that the fuel system is functioning, as long as the pump runs (See #1).

 

[Espresso]

Thank you for the reply. Well, I think I found the problem. I didnt post more here, but in another thead(I was rambling & didnt update this one yet).
Well. When it did stall today( it lost fuel pressure). I got it started rather quickly. I continued on my way to get my wife( about a mile) & when I get there i'm DUMPING coolant. I mean BAD. I get it home( Live 2 miles from where she works) & find out the lower intake gasket is blown( the outside coolant passage on the right side leaking behind the alt).
I just got in from getting all the part needed to fix it & taking it apartMy god are th eintake ports carboned up..whew). I go to take off the lower intake & the bolts WERE NOT EVEN HAND TIGHT. I took them out by hand & lifted the intake right off. The gasket was also broke in half around the coolant passage.
What I dont understand is how is it possible fo rme to be pulling 19hg vac@ idle with the intake leaking like this...I dunno.
So tomorrow i'm putting it all back together & see what she does.

As for the lower intake bolts being loose. I know it's a common problem but how do we fix it? I noticed there was no loc-tite on the threads. Would this fix it? Or is it something we have to live with?


Also I noticed the VC gaskets are metal. Are they reuseable? If not I already have new ones to put on. But figured if they are I can return these & save some cash.

 

[Espresso]

Yet another update. Ok I go teverythig put back together & it runs fine( I dont seem to see any difference yet). I've had i trunning for about 4 hours.
My one question is. On the back of the block There is a sensor where the oil pump gear goes( that is what they call it in the Haynes manual).
But in the Haynes there is no sensor on top of it. On mine there is. I can wiggle the connector around pretty good. Is it supposed to do this?

 

[Espresso]

Figured i'd update.
On the 1st I replaced the Ignition lock. It stalled on the 2nd. So I know it wasnt that.
The 3rd I went to the junkyard & got a TON of fuses, relays, ect.. I found 1 XLT that had ALL NEW relays so I got them all( I assume they probably had a similar problem, as I was about to do the same thing).
I replaced the Fuel Pump & EEC power relays. I took the old ones apart & let me tell you...NASTY!!!!!! All boogered up & rusty.

The truck hasnt stalled since. I still cant read the codes so tomorrow i'm going to pic up an ECU.

 

[Espresso]

WHOOO HOOOO
Finally got codes. The PCM was bad!!

Went back to the bone yard & took out a PCM from another 94 & all that was different was the digit before last( mine was a NB this is a MB). I plugged it in at the yard, started it up & the rough idle went away immediatly, & the pick up that I thought was great before is even better. That thing will scoot now. Cant wait to put in the 3.73 LSD
Monday i'm going to make a package deal with the owner for the entire 94. I cant remove it from the premisis so I have to leave it there.
Getting the running boards( the FULL legenth ones from fenderwell to fenderwell) the LSD, engine & tranny( time for a build up) & anything else I can get off of it( doors, harness, ect)

Time for a engine code & diag thread