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D1 4.0 V8 Fuel injector how to?

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Old Mar 29, 2025 | 11:54 AM
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Default D1 4.0 V8 Fuel injector how to?

I’ve tried searching for a guide to replace the injectors in a 97 D1. Can’t seem to find anything? The throttle and cruise linkage looks to be one of the more tricky parts of the job.

I’ve attempted this job awhile back, but failed. I removed all of the bolts to the upper plenum, and couldn’t get it free. Beat on the plenum for a long time, and it just wouldn’t break free.
 
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Old Mar 29, 2025 | 01:47 PM
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RAVE manuals are the best guide. Plenum has 6 bolts. Some use a 2x4 to lever on the throttle end, against the valve cover to crack it open. Linkages are easy to simply remove the cables, fidgety little clips (don't drop 'em). 6 more bolts on the trumpet base. Remove the coil pack and fuel rail, try not to spill too much gas. Blow sand off the injectors before removing them.
 

Last edited by JohnZo; Mar 29, 2025 at 01:51 PM.
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Old Oct 30, 2025 | 10:57 AM
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Originally Posted by LKNSB
I’ve tried searching for a guide to replace the injectors in a 97 D1, including the bosch injektor, and can’t seem to find anything? The throttle and cruise linkage looks to be one of the more tricky parts of the job.

I’ve attempted this job awhile back, but failed. I removed all of the bolts to the upper plenum, and couldn’t get it free. Beat on the plenum for a long time, and it just wouldn’t break free.
To remove the upper plenum on a 1997 D1, fully disconnect the throttle and cruise linkages, vacuum lines, and electrical connectors. Check for any hidden bolts, then gently pry the plenum free rather than beating it. Having a helper guide it while wiggling usually makes removal much easier.
 
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Old Mar 8, 2026 | 09:58 PM
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I'm about to change out my fuel injectors as I believe one of them is causing a misfire. I have a few questions:
  • Can anyone confirm if I need to have any special tools for this job?
  • Can I get away with leaving the fuel regulator connected to the fuel rail?
  • Do I need a replacement gasket for the plenum cover?
Any tips is appreciated.

 
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Old Mar 8, 2026 | 10:39 PM
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I did this a couple of years ago, so from memory. (P38 Range Rover 1997, so same engine). No special tools and I believe the sealing is done with RTV. IIRC I did use a 2x4 block to free the plenum.
 
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Old Mar 8, 2026 | 10:40 PM
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And I did not remove the regulator.
 
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Old Mar 9, 2026 | 10:16 AM
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After trying several types of sealant, my favorite is Loctite 577 (or 567 works too) for the manifold to trumpet base seal. Also works for the upper plenum. I use the Loctite Activator on the aluminum parts as well, but not required. Permatex Ultra Gray also works, but the Loctite cleans up better.

Tool-wise, just make sure you have the right length extensions, maybe a magnet if a nut drops out. Blow the sand away from the injectors prior to removal. Basic mechanic stuff.

Which brand of new injectors did you opt for?
 
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Old Mar 10, 2026 | 09:02 AM
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Thanks for the responses. I think my last question at the moment is, what is the "Trumpet Base"? I've looked this up but not finding a clear visual or answer.

Can I get away with just removing the intake plenum to access the fuel rail bolts and lift the fuel injectors out for a swap out?
 
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Old Mar 10, 2026 | 06:04 PM
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Remove the upper plenum and you will see the eight trumpets.
 
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Old Mar 11, 2026 | 12:23 PM
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Just did this job a few months ago... swapped in some Volvo injectors as a slight "upgrade". Don't need to remove the FPR but you will need to open the feed and return lines. A good set of flare nut wrenches will be indispensable here. As far as cruise/throttle linkage, I followed the instructions in the factory shop manual and took reference pics beforehand. Wasn't as bad as it looks - actually you really don't have to touch the cruise stuff, other than pulling the vacuum line off. It's really the throttle/kickdown cables. Here's a few pics of mine....









 
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