I'm about to give up. I need help.

Hey all,


I'm about one more skinned knuckle away from giving up on the Thunderbird. Everything that i check is within spec, but the car still cannot make it to the fucking gas station and back without breaking up. On paper, the car should run nice and smooth, without any hiccups, but for some reason it DOES NOT.

I've checked everything that I can think of, and I'm absolutely stumped. I've NEVER had an issue elude me for this long without resolution. I need help. I have all the tools I need (with the exception of a timing light) but what i need is someone to look at it with a fresh set of eyes. I'm not ruling out the possibility of a fucking reward should the issue be found. I'll be messing with it during the day on weekdays, and probably all weekend long. I CAN drive it short distances, (Drove it home from Mazo) so I'm willing to drive the piece of shit somewhere for someone to look at. Unfortunately, 99.9% of shops out there have nobody that knows these 2.3T engines, and plus i'm pretty much a broke motherfucker after trying to get this damn thing running.


If anybody can help, Please let me know. I'll provide the fucking beer as well.

you where in Mazo....you should have swung by. Opinions are free. If you are that deep into it and jammed up maybe we can figure it out. BTDT...

Whos place in Mazo did you have it at? Not bashing anyone....just curious so I know if I bump into them I can ask them what you had going on and what they did or didn't do. Just better to talk to who was in it instead of them saying to you and then you saying to me, it takes one word missing or lost in translation to make everyone confused.

By buddie, Aaron King. It was at his house, so no shop or anything.

Blackout wrote:

By buddie, Aaron King. It was at his house, so no shop or anything.

Name rings a bell but the face is escaping me....

Regardless. I am knee deep in fleet work suddenly but give a top to bottom list of what you have done from start to finish since this issue came about. Every stupid little detail you think may not be important. If my world becomes a happy place I may be able to give you some time late this week at the end of the day just to give it a "once over" and a idea or two you may not have thought of.

No, I'm no expert on the 2.3L but I've busted enough knuckles in 20 years of wrenching to know we must make sure the basics are there before getting worried about anything else. If I don't know the answer to your issue I won't bullshit you, I'll just plain say "I don't know". If I knew everything I would be in Vegas at Caesars counting cards with a cold drink in my hand.

If you want to PM that is fine, throw the list hear also if you want. Extra eyes always help.

wherev is the car at now?

LOL thanks man.


Okay here it goes.:


2.3L Turbo, 98K on the clock.

Modifications:

Gutted Upper intake
Knife Edged Lower
65mm Throttle Body
EGR Delete
Steeda AFPR
Ported E-6 manifold
T3-To4E .57trim compressor, .48 Turbine
Stainless braided large diameter feed and return lines (oil)
Semi-cold air intake
Modified Air flow Meter
Hallman Pro RX MBC set 10PSI
Cleaned and Flowed Stock Injector (36PPH)
Stinger FMIC kit
Walbro 255 HP pump

What we've checked so far:


Ignition Timing is set at stock 10* BTDC.
Vac/boost leaks - NONE found
Charging system - Normal operation with correct voltages
Fuel System: NEW walbro pump, Regulator checks out, Fuel pressure increases 1 for 1 with boost as it should. We've added and subtracted a bit of pressure here and there, with no changes. Return line is free from obstructions. Injectors were pulled and re-checked, no flow issues and spray pattern is identical. They also get the correct voltage they need to open and close.

Computer: Swapped computer with a known good unit out of a running car, no change. All grounds were checked and cleaned up. All signal return wires from engine sensors are reporting correctly, and the signals from all sensors are reporting correctly to the computer. I noticed that my alternator was charging a bit high, so i swapped that out today. We added/changed/eliminated the BOV with no change in how it runs. We swapped a known good distributor into the car with a known good ignition module on it. No changes in how it ran.

We noticed that if you put a timing light on the coil to dist cap wire, you can actually see the coil miss a pulse or two in time with the car's idle miss. I swapped a new coil into it, with a new coil wire, no change. I also tested the voltage at the + side of the coil, and it had steady battery voltage, no breaks. I did a shake test on every single set of wires i could get my mitts on, no perceptable changes in the way it runs. Compression checks out, and all 4 cyl are well within factory specs.


I found out that the cam timing MAY be off by about a tooth. I'm currently in the process of re-timing the cam, and I should have the result of that tommorow.


What the car is doing: At idle, it misses pretty good. if you free-rev the car, you can SOMETIMES get it to miss without a load on it. When you take it down the road, you can build about 5 or so PSI before it starts misfiring and bucking, causing you to get out of the throttle. If you press it down more when it is misfiring, it will sometimes clear up and stop the miss, but 9 times out of 10 it starts doing it worse. If you try to hold a steady speed on the highway (IE 55MPH on a flat road in 5th gear) it will start mis-firing, getting progressively worse until you have to get out of the throttle. It does this at any speed/rpm combo as long as you are trying to hold it steady. We also see a low vac reading at Idle.

brngrhd wrote:

wherev is the car at now?

In Sun Prairie, sitting in my apartment's driveway.

Hey dude, when exactly did this problem start occurring?

It started last year, when we did the turbo, manifolds, fuel system, intercooler.... We thought, "hey, lets look at what we just put on it " and all of it checks out. I thought that my issues were from a worn to hell cam last year..... and I was right that it was worn to hell, but now..... its gotta be something else.

So it started pretty much right before I met you when you bought my JL amp then? I remember you talking about it then.

I am assuming you don't have a wideband 02 sensor setup (even a narrowband might tell you something). I would consider this. I hate not having a WB in my cars, it makes diagnosing in the "field" way more difficult.

What does your fuel pressure look like?

I assume you have tested your compression?

What year is your T-Bird again? Sorry, I missed and didn't see it before.


Is it a modified ECU and can you still put a factory scan tool, or aftermarket scan tool on it to read the data?

What have you done on the secondary ignition side of it? Scoped it at all? Did the timing change when the spout connector was pulled?

Any other new parts on it to fix the issue.?

240sxguy wrote:

So it started pretty much right before I met you when you bought my JL amp then? I remember you talking about it then.

I am assuming you don't have a wideband 02 sensor setup (even a narrowband might tell you something). I would consider this. I hate not having a WB in my cars, it makes diagnosing in the "field" way more difficult.

What does your fuel pressure look like?

I assume you have tested your compression?

Yep, thats right about the time it started! I don't have a wideband setup in it, but I have everything for it. I just have to get it to Nate to weld the bung in. Fuel pressure is steady and set about a Lb or 2 above factory. It increases with boost like it should. Compression was 155, 150, 145 145. The 155 is cyl # 4.


Lilwillie:


Its a 1988. The ECU is factory stock , so you can put a code scanner on it. I'm doing this tomorrow, since I had a CEL today at idle. We havn't scoped anything, but voltages are checking out, and yes, the timing pulled back to 10* BTDC when the spout was pulled. Thats factory setting for this car, and it re-advances like it should when you plug the spout back in. We swapped in a known good distributor and TFI module, with no change in how it ran. It now has a new coil and coil wire, with no change.



Today I finished up re-timing the cam. I may still be slightly off on it, but the car actually RUNS better. I can actually drive it around a bit. You can still feel it misfiring and breaking up at cruise, but it doesn't break up as bad. SO the net result of re-timing the cam was that the problems are still there, but diminished greatly. I'm guessing since the cam timing WAS off, it made the missfire more noticeable. Right as i parked it for the night ( had to go to work) I got a CEL and it ran pretty rough at idle. I stabbed the throttle a couple of times, and got it to miss as I pressed the peddle in. It cleaned up as the revvs got higher, but If i stabbed it good, it would miss like crazy for a couple seconds. This HAS to be an ingnition related misfire...... The fuel system completely checks out. I'll pull codes tommorow AM and we'll see what we have.

You sure you dont have an issue with the intake or some of the turbo connections? Kinda sounds like it could be a tiny vaccum leak. Just an idea.

if you have replaced all this stuff and it is still F'd up i say you may have a wiring problem but the fact that is got better after you reset the cam makes me think that your cam could be ground wrong. you know anyone with a degree wheel?

We pressurized the intake and such from the air meter forward, and other than a slight pressure leak at the throttle cam, there isn't anything else. (That leak at the TB is one that I've seen on every TB, new or used.... pressure slowly leaks past the throttle shaft.)

The coil missing a pulse thing is still present..... so I'm thinking its an ignition issue at this point. The cam *could* theoretically be ground wrong, but the vendor I bought it from is a real stickler about quality control. Nobody i know has a degree wheel. It would have been nice to set this up with one, so i KNOW its dead nuts on. I'm starting to think that the cam being off made the missfire worse. Thats why after I set the cam up like it should be, it didn't fix the miss.

Have you done a leakdown?

Some engines use inputs from the cam sensor(s) too affect timing. So If your cam is ground wrong, theoretically it could be contributing to an ignition related misfire. At least thats what they been teaching me up at the college.

LOL This car is WAAAYY to old to have a cam sensor .


Blown91LX- We did a leakdown test after we did compression.... and it was in spec, something like 8% loss I think. I did the math, and wrote it down, but I don't have it with me.

The more you discuss it the more it sounds like a primary or secondary ignition issue. Time to scope it and see which cylinder is messing up. I have a quicker way of checking also, nice little ignition toy for confirming voltage and spark on the secondary side.

Anytime in the afternoons...wed,thur,fri...after 4-4:30 til 6 stop by if you want and I'll take a listen and quick look and see if a fresh set of eyes can tell you anything

Did you try replacing the MAF as I didnnt read if you did or not??

Blackout wrote:

LOL This car is WAAAYY to old to have a cam sensor.

No its not, my 91 nissan had one

LLcoolJames wrote:

Blackout wrote:

LOL This car is WAAAYY to old to have a cam sensor.

No its not, my 91 nissan had one

I don't think he was referring to when cam sensors came about (which was very long ago by the way) just that in this particular make and model they still took the cam signal off a pickup in the distributor.

You are right Lilwille: Thats exactly what I meant....LOL

I wouldnt doubt that it is ignition related. I'm convinced of this by the fact that you can watch the ignition pulses "Skip" when it misses in neutral (looking with a timing light on the coil wire).

I noticed something else today that might be a clue as to whats going on. I can build boost in neutral by high-revving it. From what I know, you should only be able to see a tiny bit of boost (like 1psi tops) if you rev it in neutral, since there is no load. I can make 15..... and i've seen it spike as high as 20! This tells me that the damn cam timing is STILL off. It must have been really jacked up before, since my symptoms have improved, but i must still be off. I'm going to shelve the adjustable gear for now, and time it with the stocker just to see if it helps. i had it all apart yesterday, so it shouldn't take long LOL. If anything, I'm off by about a tooth or so now. I also noticed something else. According to my vac gauge, it sits right around 15HG at about 1100 rpms. After revving the piss out of it, it starts missing horribly at idle. My Vac goes down to about (hg while this is happening. If I rev it and let the throttle snap shut, it snaps back to 20-21hg like it should, and then evens back out at 15.


I think this may be an ignition issue coupled with cam timing. I'll have to see about bringing it out sometime, as I'm curious to see what the secondary side of the ignition is actually doing..... and to confirm that its missing pulses.

Bod89lx wrote:

Did you try replacing the MAF as I didnnt read if you did or not??

No MAF, it has a Vaned Air meter.... same concept, but instead of a heated wire, its an actual spring loaded door with a potentiometer on it. Same voltage range though. I've actually replaced that 4 separate times.... and finally got a good one.

well the fact that you can build boost with out load could be that your pumping fuel into the exhaust housing and it could be lighting there and spinning the turbo....... this is actually a common thing to do with the big boys to get those huge turbo's to spool. im not saying that is what you got going on but it may be.......