I bought another Mark VIII...does this sound like IMRCs?

K

KyleH

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Well after two years with my WRX, I decided to buy a Mark VIII project car so I'd stop modding my WRX. I discovered that while on the highway when I floor it it is basically limited to 4200RPM or so. I am thinking the IMRC arent opening. Does this sound right? It drives and shifts fine but when I got WOT it simply revs up to about there and then stops. It feels like part throttle cruising is normal. Thanks in advance.
 
I would think even if the IMRCs did not open you would still accelerate but at a slower pace?

Perhaps the cats are partially plugged?
 
What year is it? If it has a vacuum leak the IMRC stick open in Gen 1's resulting in poor throttle performance at slow speeds. They open at 3200 RPM by vacuum (Spring held shut). Without more info just guessing.
 
Its a 93 with 58,000 miles. I just seafoamed it. I need to take it on the highway but its not yet registered. Now I am thinking the transmission might be slipping. When it get on the power it just does not accelerate. It'll hold speed though.
 
If the transmission is slipping then it WOULD rev higher then 4200. If the IMRCs are an issue I'd throw codes.

Always check codes first, even if there isn't a light.
 
Im going to have to go with cats too. Drop the exhaust and see what happens. If it isnt the problem, your not really out any money.
 
Are the cats on this car welded to the headers? I am cleaning out my garage tonight to make space for this car. If I have time left I will unbolt the exhaust and also take it for a longer test drive and see how it does.
 
That sucks if it is the cats then. I am going to have to make a set of headers if I go through with the motor swap anyway. If it is the cats that's just another reason to get on with it.
 
I know I shouldve pulled codes already but I took it for a little test drive again tonight.

The car is not yet registered so the test drives are pretty short. Drove it about 2.5 miles to get it warm and then went to an empty industrial park and floored it along a long straight, rolling at about 30 mph. The RPMs after seafoaming it went up to >6000 (this car has a chip so I assume it has had the rev limiter removed or increased) and seemed very late to shift. When it shifted I could hear a bit of a squealing. Car basically did not accelerate appreciably from 4000-6000RPM although the engine rpms climbed like you would expect them to under load. RPMS climbed, it shifted hard, and then it started to accelerate for a bit and then it felt like it downshifted (lost gear) and the rpms went way back up. It felt like it just slipped out of gear.

I am thinking the IMRCs were sticking and now that I seafoamed it the RPMs will climb fine but I have a trans issue.

This car has 3.73s, posi, a blue oval chip and is supposed to have a Jmod and replaced 1-2 accumulator pistons. The guy claimed the trans has been rebuilt once with heavy duty clutch packs.

Here is a copy of the craigslist ad detailing the mods:

Lincoln Mark 8 1993 - $2750
Date: 2011-08-03, 8:59AM EDT
Reply to: [Errors when replying to ads?]
93 Lincoln Mark VIII

58,000 miles. Yes only slightly less than 58,000 miles
A/C is ice cold...
Tan leather interior is in fair-good condition.
Has original floor mats.

Many Extras...

32 valve V8 engine with Blue Oval chip with programming for regular or premium
(I always used Valvoline synthetic motor oil)

OEM Air-ride suspension with upgraded urethane bushings on front strut rods
New OEM upper control arms with new ball-joints
New OEM rear shock mounts
Recent front-end alignment

New HID headlamp conversion (OEM-96)
Replacement Temperature Control Panel (OEM-96)

18" Cobra mustang rims with 245/40Z18 FK451 series Falken tires
Cobra Mustang 4-wheel Powerstop cross-drilled rotors and front PBR 2 piston calipers with Russell brake lines
17" OEM Cobra Mustang spare tire

New Ford motorsport 3.73 limited slip rear-end with poly mount bushings
OEM speedometer gear installed to match gear ratio, as well as, chip programing

OEM deep-sump tranny pan; OEM replacement pistons and springs in transmission w/ J-mod
( Castrol Mercon V synthetic transmission fluid )

Like-new battery / "Exotic Wood Dash" burled walnut parts on tan interior / some new chrome and new trunk emblem

This was my project car and all replacement parts are NEW OEM, not from junk cars!
Just the new parts are more than I am asking $$$
I subscribed too and referenced modifications, part numbers, etc. from "Lincoln's of Distinctions" car-club web-forum.

Clear-coat is faded on hood and roof but relatively new paint on rear bumper, trunk and rear quarters.

3n33m23o65Y15V05U3b75a1b6d616e4dd12f5.jpg
3n43o43l25Y45X55R1b75b2af23514aa11a4e.jpg
Click to expand...
 
Well, test driving it over and over isn't going to solve anything.

Start with the basics. If you think its engine related, pull codes. If you think it's transmission related, check the fluid. Go from there.
 
KyleH said:
Well after two years with my WRX, I decided to buy a Mark VIII project car so I'd stop modding my WRX. I discovered that while on the highway when I floor it it is basically limited to 4200RPM or so. I am thinking the IMRC arent opening. Does this sound right? It drives and shifts fine but when I got WOT it simply revs up to about there and then stops. It feels like part throttle cruising is normal. Thanks in advance.
Click to expand...

driller said:
I would think even if the IMRCs did not open you would still accelerate but at a slower pace?

Perhaps the cats are partially plugged?
Click to expand...

i had one not opening, it kept pulling, just real real slow around 5500.

Roadboss said:
What year is it? If it has a vacuum leak the IMRC stick open in Gen 1's resulting in poor throttle performance at slow speeds. They open at 3200 RPM by vacuum (Spring held shut). Without more info just guessing.
Click to expand...

gen 1 imrc's are spring loaded open, and the vacuum shuts them.
releasing the vacuum at 3200 opens them.

edit: also. a gen 1 won't throw imrc codes. it has no way of knowing whether or not they open. i had one that i know did not open. no code.
 
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Ill try to make a video of its symptoms tonight.

Hey Chris, have you ever run your mark viii at the track? What does it run in the 1/4?
 
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