I'm starting to hate this mark 8

ok I'm just copying and pasting this into both websites. lately I've been having problem after problem after problem. once 1 thing goes wrong and fixed something else breaks. so heres my problem now. I installed a new 255lph pump and my gas mileage went up, I was getting around the city/town about 15, closer to 16 after being around 12-13 all winter for the same driving. now that has returned to around 13.5. heres what could be causeing that, Untill the car warms up completey and the temp gauge is in the middle, I cannot get on my car.. If I try to step on the gas it doesn't wannna move, its like the rpm,s go up, then it cuts off, then goes up again.. the only way I know how to explain this is if you're ever low on gas and you step on it, you kinda get hessitation. thats whats happening, but its only when the car isn't at normal temp. I've also heard that the car has sensors and such when its cold that don't turn on untill it gets hot... but the car has never done this in the year and a half I've had her. so something happened that is causeing this. thanks oh and happy easter

Steve

RE: I'm starting to hate this mark 8

What parts have you changed and checked out on the car, and are there any codes? Also what year is it and what is your mileage?

RE: I'm starting to hate this mark 8

119,000. I don't know if I filled out my profile for this site yet. umm new wires plugs, fuel filter, 255lph pump, lms chip, new cam sensor, lms maf.. I changed the mlp sensor and I don't know if it has anything to do with the tranny. I had the tranny serviced when I bought the car at 105,000 but it shifts perfectly. and it isn't the original one, it was re-built however I don't know when. thats all I can think of right now. umm It just seems like its something to do with the fuel system, but I don't get why it would only happen when the car isn't at normal temp. and why all of a sudden did this start to happen. I know my alt is taking a crap too, but again why would an alt be causeing the car to malfunction only when the cars "cold", it puts out enough volts as well. the other day when I first noticed it I was merging onto a empty hwy and I decied to floor it. so I got till 90mph and thats when it happened, I was scared cause I thought the car shut down, itw asn't untill I started to really slow down that I knew itw as still running. No chk engine light either

RE: I'm starting to hate this mark 8

I see you have a lot of moods. The first thing to do is to make sure all you connections are air tight upstream the MAF sensor.
Also have you ever cleaned the mass air wires? And do you know if your O2 sensors are the original? Have you changed the spark pugs, and if so what did they al look like?

RE: I'm starting to hate this mark 8

Steve,

When I first start my Mark (with no mods) in the morning, after it has been sitting outside all night, and I get on it within a minute or two of first starting it, I also have hesitation.

The hesitation (upon flooring it) is more of a quick series of wahhhh...wahhh...wah...wahhhhhhhhhhhh!

It only happens when the engine is DEAD cold, and never any time after that. Sort of reminds me of the old carbureted days.

Is this what you are getting?

RE: I'm starting to hate this mark 8

my 02's have been changed like 3 months ago. umm my plugs looked alright when I changed them. the car feels like it will stall out when I get on it till it warms up. it kinda does what you explaned but if it didn't do it since I had it, why would it start now? that doesn't make sense, to me something must've happened to cause it. i'll also check my maf wires, but again if it is a connection, why does it only happen when the engine is cold, or only happen within a few minutes of starting. I don't jump in my car and drive, I let it idle for a min.

RE: I'm starting to hate this mark 8

I have the same problem when my car is cold too. Mine is a 95 Mark VIII, 106,000 miles and bone stock. I have done Tranny Service with 1-2 upgrade and synthetic fluid. It is almost like an air lock in fuel delivery. I just back off until its warm, but its not right. I know that much.
Could this be something to do with exhast system? Maybe the cats are becoming pluged? Or an O2 sensor causing problem?
Never would I hate my Mark though! Hate is a bad word. You should be ashamed of yourself.

RE: I'm starting to hate this mark 8

nah I really am starting to hate this car. Ithe past few months I have been putting so much money and effort into it. and it might not be major stuff, but all the little things add up you know. actually I think I might have fixed the problem only I'm not sure. I'll keep ya updated later on today.

RE: I'm starting to hate this mark 8

When I start my car in the morning and back out of the drive it's fine, when I put it in drive and gently press the pedal it stalls a bit.. not completely but it hesitates some. There's a certain pedal position that makes it the worst but before (less gas) and after (more gas) than that "G" spot and it accelerates as expected. What's the deal? It doesn't do it when it's warmed up.. just cold. Nothing to be concerned about? Is it totaled?

RE: I'm starting to hate this mark 8

I strongly disliked my car for a while... so much I was shopping for a replacement...

Then, I started looking at the $500 a month car payment and realized I could fix the hell out of my car for $6000 a year!

I don't hate it anymore... I look forward to repairs, they are a chance to make it better...

and so far this year I am about $1500 ahead of where I'd be with a new car....

Scott

RE: I'm starting to hate this mark 8

I'd look to the EEC, it is probably compensating for the mods.

RE: I'm starting to hate this mark 8

Have any of you run a code tester on your vehicles? There are a number of sensors that work together with the fuel injection that go into making the car run when the engine is cold, kind of like the chokes on carbureted cars. I know there are sensors that measure the ambient temperature, the temperature of the coolant and when compared the air/fuel mixture is richened, as a choke would do. I hate to say it but sometimes paying the dealer or reputable repair facility to run diagnostics on your car is worth every penny especially when your frustration level is extremely high. Hey, these cars are complicated and unless you work with new automotive technology everyday a trained professional could be your best bet and best bang for your bucks!

RE: I'm starting to hate this mark 8

Then, I started looking at the $500 a month car payment and realized I could fix the hell out of my car for $6000 a year!

Scott

Click to expand...

Finally! Somebody else sees the light.......Bought my car for $3600 where others were selling for $6000. I think the 163000 miles (over 190K now!) had something to do with it because it's a fairly straight car. With a lowball price, I can afford to put some money into it!