Results of compression test on '96 DA

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sprocket

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1) 160
2) 160
3) 155
4) 160
5) 160
6) 175
7) 155
8) 160

I could maybe recheck #6

Looks like the head gasket is OK.

The car starts hard. All plugs had some oil on them. I should do the valve cover gaskets and grommets but I doubt if that is the cause of the hard start. I previously swapped the FPR for another spare I had. It could be bad. I have yet another spare. I could try that since it is so easy to do. Maybe I should post a video of the hard start. It's pretty horrible sounding.
 
I'm not sure what you mean by hard start.

Turns over like mad but wont fire?
Hard to turn over and sounds like hell?

I am guessing the second.

If its the first check fuel pressure at the rail at start up.
If its the second check all power cables, at the battery and down at the starter.

I agree, head gaskets look OK.
 
It's hard to start like a snow blower is hard to start. I starts to catch then dies. Then it is much harder to start after that. When it finally catches it spits and sputters until finally it clears the fuel. Then the RPMs stay up above 1000 for awhile, like maybe 30 seconds to a minute, then come down. There's nothing wrong with the starter.

I also hear kind of a wooshing or howling sound in the air cleaner, which goes away after a minute.

But this doesn't always happen. The last two starts were a slightly slow and the engine stumbled just a bit then smoothed out.
 
Dumb question, are you sure the firing order is correct and the coils are good?
 
97MarkJA said:
Dumb question, are you sure the firing order is correct and the coils are good?
Click to expand...

The firing order is good but it is the '93-'95 order. For some reason they changed it slightly in '96 but it makes no real difference since two cylinders fire together. I guess for the heck of it I could change it, but I have researched this and there are those that have done it either way and it makes no difference. I actually have a thread on this topic.

I assume the coils are good because there are no current codes stored for misfire. There was a code for cylinder 6 misfire right after I changed the injectors but I assume that was due to vapor lock or something that cleared after running with the new injectors for a very short time.

After starting without too much trouble a few times it started very hard the last two times. The last time I tried just turning the key on and waiting a little while before starting. That was my friend Tim's suggestion to build fuel pressure, but if I remember right, it can have exactly the opposite effect because I believe the fuel pump shuts off if the ignition is not turned all the way to start after a few seconds.

I'll get a video of it tomorrow morning. Make sure your breakfast has fully digested before watching. I think I will check the fuel pressure again tomorrow. I did it before and I think the pressure might have been a little low, like maybe 35lbs, and it dropped to like 12lbs in an hour. I'll record it with just the pump on, during the start, while running, and every 10 minutes for an hour after shutting it off.

I also bought supplies for an oil change tomorrow. I bought Motorcraft filter FL820S with the anit-drainback valve and 5w30 full synthetic oil. I'll see if that helps the start any.
 
Fuel prime only last for less than 2 seconds. Should show 39/40lbs with a good pump. Unfortunately these model year vehicles can have large misfires, and not show a code. They are very liberal with the programming. 2003 up vehicles are much les tolerant.
 
Psychostang said:
Fuel prime only last for less than 2 seconds. Should show 39/40lbs with a good pump. Unfortunately these model year vehicles can have large misfires, and not show a code. They are very liberal with the programming. 2003 up vehicles are much les tolerant.
Click to expand...

+1. My 98 had a coil totally dropping out on it. You could feel it stuttering under load. I had NO cel.
 
I can swap in the coils off the other car. I'll do the fuel pressure test and change the oil. I'll post the results of the fuel pressure. If it still looks like it's the coils and not the fuel pump I will swap the coils. Who knows, I might just get up tomorrow and swap the coils first.

Thanks for all the help guys.:)
 
Today we determined that the FPR was junk. The fuel pressure would immediately drop back to zero after energizing the pump. I took the brand new FPR out of my other car and installed it. Then the fuel pressure went to about 39 lbs and dropped back to 15. Later we tried it with a different gauge and the fuel pressure dropped back to about 20 lbs. In this video the car wouldn't start at all and this is with the new FPR. While cranking the pressure was up around 40 lbs. I did get it to start about 15 minutes later. After shutting it off the fuel pressure gradually dropped to about 20 lbs and held. Over an hour it went down to 15 lbs. It started pretty easily after that, but I have a feeling the problem will return.

The sad irony is that we used my other Mark for comparison and it only has about 30 lbs of fuel pressure. The DA holds at 35 lbs while running. Long term fuel trims on the other Mark shows that it is always having to add fuel which makes sense if the pressure is low. BOTH cars might need fuel pumps. The non-DA one needs one for sure.

Here's the video. Horrible quality from my phone and Tim doesn't know how to hold the camera. I also went way too long before giving up starting it. Hey, the battery is good!
'96 Mark VIII DA no start - YouTube
 
How old is the fuel??

Have you checked the CPS plug yet? Make sure its clean. Also peal back the loom a couple inches and make sure the wires insulation isn't gone

Hold key for longer intervals ..rapid bursts of key strokes is bad for the starter

Do you have a spare ECU to try? Is this car chipped?
 
Fuel is fresh. Haven't check the CPS. I don't know if it is chipped but it might be. The ECU doesn't record long term fuel trims which I find very strange. They read zero. They possibly could have been turned off in a tune to avoid a CEL. How can I tell if it is chipped?

Yes I have a spare another ECU in my other '96. I thought there were three different ones for that year though. I also don't want to "fry" my good computer if there is any risk of that.

I do hold the key longer. That was Tim letting up to soon. I would have got it to start if it were me trying from the beginning.
 
Another question: When you say CPS what are you talking about? I believe CPS is cam position sensor also known as CID sensor, and CKS is the crank sensor.

I have seen the crank sensor referred to as CPS but I think that is wrong.
 
You have a crank position sensor and a cam position sensor As cheap as they are, it couldn't hurt to replace both or swap from one car to another and swap out the VLCM / VCRM and ECU's to see if it changes anything. Try to start it after each part swap to see which one might fix it. Just an idea since you have a spare 96 setting there or I'm taking it that you have an extra one setting there.
 
The crank position sensor could be a suspect because this car hasn't always started hard. This problem developed during the time I have been working on it so anything I have been working near becomes suspect. I could have gotten coolant on the crank sensor connector.

For what it's worth, I have no stored codes.

I don't mind swapping parts as long as some goofy electrical issue doesn't fry my good parts.
 
You may have the same problem I did. About 2 or 3 months ago, my car developed a hard start problem out of the blue. My fuel pressure would also drop back to zero. Unfortunately it was also hard to get any fuel pressure readings. Took many turns of the key to show any pressure. Turns out the pump was good, but the hose connecting the pump to the hat-nipple had been overcrimped at the manufacturer. Thus pinching the hose. It finally split open. I think I posted a picture on here.
 
Psychostang said:
You may have the same problem I did. About 2 or 3 months ago, my car developed a hard start problem out of the blue. My fuel pressure would also drop back to zero. Unfortunately it was also hard to get any fuel pressure readings. Took many turns of the key to show any pressure. Turns out the pump was good, but the hose connecting the pump to the hat-nipple had been overcrimped at the manufacturer. Thus pinching the hose. It finally split open. I think I posted a picture on here.
Click to expand...

I have change the FPR and the pressure no longer drops rapidly to zero. It drops some but slowly, exactly like my other Mark does and it starts fine. I mean my other Mark starts fine.
 
Your ECU is to the left of the brake pedal, the silver box.. remove the black clip and pull the ECU down.. there's a slot on the edge that sits closest to the firewall.. if there is something stuck in that chip slot.. its chipped. If its chipped-remove the chip..
 
Checked engine vacuum. It was good. Compared it to the other car and found a vacuum leak on that one, which I fixed.

Swapped ECU's. No difference. The ECU is not chipped. Live data on the DA still does not register any long term fuel trims (with either ECU) and at idle the short term fuel trims show that fuel is being added to counter a lean condition. The STFT are often above 20%. At 2000rpm they go to a good range.

I could try a different MAF sensor. I guess I will go buy a cam and crank sensor.

I don't really understand the hard start. The car is clearly massively flooded when it finally starts and right after starting the STFT show a lean condition. I suppose it could be a false lean and that could be the MAF sensor. I'm surprised there are no stored codes at all.
 
Tried a different MAF. No improvement. Drove on the highway and watched live data. Bank 2 mostly has positive numbers in the 10-14% range for STFT. That means that bank is wanting to run lean or the computer thinks it is.

Another weird thing is that the scanner is reading MPH at 58 when the speedometer shows 62. Also, the coolant temp is showing steady at 165-167 which seems a little high considering there is no thermostat. Maybe not.

I think the hard start is getting worse. Now it only seems to need to sit for maybe an hour before it starts hard.
 
Have you ever changed the fuel pump?
 
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