Serious misfiire issue

[captinsho]

Okay any help I can get here would be greatly appreciated. I am a member of the Delphi Sho forum and was told you guys reaaly know your stuff, so I could use some of that stored up (definitely not useless) info. I have a 94 MTX w/96k. Lately is has been misfiring. My check engine light has been on also. I ran the codes and I got 1: KOEO I GOT CODE 126 (MAP OR BARO SENSOR OUT OF RANGE) AND CODE 219 (SPOUT CIRCUT FAILURE, TIMING DEFAULTED TO 10 DEGREES-FOLLOW CODE 213 DIAGNOSIS) 2: KOER CODE 111 (SYSTEM CHECKS OK). My brother took the car (knows more about engines than I do plus has a shop to work on them) and reconnected something I must have missed when I did a clutch job a couple of months ago. My check engine light went off after that but it still ran poorly. Next he pulled the plugs and noticed that all the electrodes on my 5 month old BOSCH platinums were "burned" off. He said he had the same problem on a set of BOSCH platinums he put in an ****** GT he owns and he has heard that some Ford engines have problems with BOSCHs. Anyway I bought new platinums (Chapions) and it made a little difference but it is still definitely not right. We also reset the computer. I plan to run the codes again and see what/if I get. I also brought the car to a local Ford dealer about 2 months ago and they got two codes: MAF hard default and air charge sensor error. Neither of these came up when I ran the codes. One possible explantation to that may be because after the Ford dealer looked at it I swapped out my Pro Flow 80mm MAF and put the stock one back in. Since I ran the codes myself I put the Pro Flow back in. Does not seem to matter if I have the stock MAF or the Pro Flow in... either way it acts the same. It is funny becuase if I rev the engine (like past 3K) and accelerate moderatley it will run strong, sometimes I can even put some real petal into it and it wont misfire but if I put a little too much petal into it it spits and back fires. Aslo it doesn't idle perfect. It will idle OK then it will start to misfire/backfire and die (sometimes) if it idles for too long... like 2 to 3 minutes. When I accelerate from a dead stop very slowly it is OK, but I have to acclerate too slowly to enter into traffic. Also if it starts to misfire it will misfire through the entire RPM range and can get very rough if I try to put any petal into it.Not sure if someone has some ideas. I would greatly value any input I could get! Gas is up to almost $2 per gallon (for premium) and I am getting about 10 to 12 miles per gallon. Also it is very annoying to have this much power under the hood and be the slowest car pulling away from a red light (while I sputtter and back-fire). Thanks in advance for your help.

 

[AutoSHO]

The first thing I would check is to make sure all the plug wires are in the right order. I cannot post the order from memory but a quick search for "plug wire sequence" should get a good diagram.

Edit: Here is the diagram: http://www.shoforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=17;t=003660#000002

Give us some more info on when this started - Did it happen all the sudden, or after you had done some work to the car? Did it get progressively worse? This will help us diagnose the problem.

<small>[ February 16, 2003, 06:47 PM: Message edited by: AutoSHO ]</small>

 

[revhardSHO]

I am having a similar problem:

http://www.shoforum.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=17;t=005524

although its still hesitating/missfiring, I think a new set of wires and plugs will clear it up(hopefully!). You can buy new wires from fordpartsnetwork.com for $83.00 (and thats OEM parts oh_my ) Just by the original motorcraft plugs also.

Like you said, once you get over 3K it doesnt missfire, and has most of its power.
Im also getting that weird MAP code, cant figure out what it is.

good luck with your problem

silas

 

[Mr Anonymous]

Definitely verify the firing order. Also do your car the favor of the genuine Ford AGSP32PP plugs -- FordPartsNetwork.com has them for $3.99/ea. The aftermarket plugs are frequently the source of many headaches, starting with an improper fit, and most are not double-platinum.

Read the codes again and make sure to clear them so you can more readily identify 'recent' codes (remove the jumper while the codes are being spit out).

You should also make sure both your SPOUT shunts are in place and properly closing the timing circuit -- when either is removed is causes the timing to default to a fixed 10 deg. BTDC, which will reduce fuel economy, although I tend to doubt it would cause the missing/backfiring problems you're having.

With 96K, do you know if the 60K service has been completed? You might have a timing belt problem which might be responsible for your issues.

 

[sdpatt]

Bosch platinums are not the correct plug for the SHO. The three coil SHO ignition system requires a double platinum plug (platinum on both electrodes) of the correct height to allow the plug boots to seal the plug wells from moisture and grit. The Motorcraft AGSP32PP is the only plug that was designed only for the SHO engine. You can get it for $3.79 ea. from O'Reilly or $3.99 from FordPartsNetwork.com.

If the engine is running at any time without misfiring, the wires must be installed in the correct order (shown below). If the plug wires are old or not the Motorcraft WR-4033 ($84 from FordPartsNetwork.com), you may be having spark leak problems. Are you still getting the 219 code?

Cylinder Order
Firewall
1-2-3
------
4-5-6
Radiator

Coil Pack Order
Firewall
5 | 1
6 | 2
4 | 3
Radiator

 

[captinsho]

Autosho...
I don't believe the wire order is wrong because it fires great sometimes and poorly at others. I am not certain when the problem occurred, it was gradual. I have Magnacore wires and I don't think they were seating propperly but I believe I fixed that. They are very snug now.

 

[AutoSHO]

captinsho:
Autosho...
I don't believe the wire order is wrong because it fires great sometimes and poorly at others. I am not certain when the problem occurred, it was gradual. I have Magnacore wires and I don't think they were seating propperly but I believe I fixed that. They are very snug now.

Try unplugging your MAF sensor and running it like that to see if it improves. If it does then your MAF is probably bad. Check all the grounds on the intake as well.

 

[captinsho]

smithsil89sho...
I just put in double plat champoins last tuesday, would they still be a problem? The car definitely does still misfire past 3K, it is just the only way I can pull away from a dead stop. Sometimes it hooks up well and does not misfire much (unless I get too hard inti the petal then it misfires terribly) other times if I do not give enough petal (needs quite a lot) it misfires through the entire RPM range.

 

[captinsho]

SHOooo...
I put in double plat champions, shouldn;'t they work? Checked both of the spout shunts already, someone on Delphi recommended that but they told me there was 3 of them. One by the coil pack and two by the firewall and passenger front strut tower. Like I said I only found the two but they were clean and in place. I got the car with just over 60K and I did not do the 60K maintenance but I put a new crank pos sensor on about 6 mo ago and I could tell the timing belt was in great condition. It had obviously been replaced before.

 

[sdpatt]

Have you seen the CHECK ENGINE light or tried pulling the EEC codes? If no light or codes, you have a secondary ignition problem: plug or wires. Get those Champion sparkers out of there. They are the wrong height and will let in moisture and grit into the plug wells past the gap in the plug boot at the valve cover. Could you have damaged a wire during the installation?

 

[captinsho]

sdpatt....
Have not had a chance to run the codes again but I will in the next 1 to 2 days. Do the Magnacors tend to have problems with spark leak?

 

[captinsho]

AutoSho
I tried with both my Pro Flow and the stock and it runs poorly either way. Is it likely they are both bad?

 

[captinsho]

sdpatt...
I dont doubt what you say about the plugs, I have heard others say that. I will tell you I have had problems with dirt/water getting into the plug wells with the stock plugs/wires in there also. I even made the grave mistake of washing the engine when I first got it and did not blow it off (younger and dumber). That wasted my stock wires so I replaced them with a new set of stock wires then later I put on the Magnacors. It ran with both sets fine but later roon poor. I had a CPS problem and replaced the stock wires with Magnacores when I did the CPS job. I have no check engine light since my brother worked on the car and I have not run the codes... yet.